Just ez french
Beginner's Opening Repertoire for Lazy B***ards - what do you recommend against d4-openings?
Queen's Gambit Declined, as long as you don't choose to play Tarrasch, Tartakower and don't enter Vienna or Ragozin in the three knights variation. You could play orthodox in Bg5 lines & semi-tarrasch in the three knights or even Lasker & semi-tarrasch ( this is even lighter on theory).
You also need a line vs the exchange and Bf4 as well, but overall this should be a nice and manageable repertoire.
The nice thing with a QGD repertoire is that after you've built a scaffold of a repertoire, later on you can add more dynamic lines ( Tarrasch or Tartakower) to play on occasion with less incremental effort than learning an entirely new opening
''Minimal theory'' sounds like stonewall dutch to me-- not always the best choice but minimal theory.
Actually, I was going to suggest Tartakower. SSCTK makes good points against it. I'll just add in its favor that playing a classical QGD , while sound, coherent and not theory rich, would likely mean defending lots of minority attacks. Minimal theory but like watching paint dry.
Bill
Since you play 1.e4 e6, you could consider 1.d4 e6 2.c4 Bb4+. Check out Eingorn (2013) A Rock-Solid Chess Opening Repertoire for Black . The kindle preview doesn't show much of the 1.d4 repertoire. ( https://www.amazon.com/Rock-Solid-Chess-Opening-Repertoire-Black-ebook/dp/B00F500AFK )
For the record it is:
- 1.d4 e6 2.c4 Bb4+ 3.Nc3 (not quite Nimzo-Indian) 3...c5
- 1.d4 e6 2.c4 Bb4+ 3.Nd2 (not quite Bogo-Indian) 3...c5 or 3...Nf6
- 1.d4 e6 2.c4 Bb4+ 3.Bd2 (Eingorn considers this most problematic for black) 3...Bxd2+ or 3...a5
- 1.d4 e6 2.Nf3 c5 3.e4 (Sicilian! I consider this most problematic for a French player, at least white is committed to the Open Sicilian) 3...cxd4 4.Nxd4 Nf6 5.Nc3 Nc6
- 1.d4 e6 2.Nf3 c5 3.c4 (English!) 3...cxd4 4.Nxd4 Nf6 5.Nc3 Nc6 (my preference would be 5...Bb4 but 5...Nc6 is okay)
- 1.d4 e6 2.Nf3 c5 3.e3 d5 4.c4 (Queen's Gambit!) 4...a6!?
- 1.d4 e6 2.Bf4 (London, he also considers 2.c3!? with the idea of 3.Bf4) 2..c5 3.e3 cxd4 4.exd4 Qb6
- 1.d4 e6 2.Nf3 c5 3.c3 Nf6 4.Bg5 (Torre, and 4.Bf4 gets a mention) 4...Nc6 5.e3 h6 6.Bh4 Qb6
Because of the possible transpositions there is some theory, but none of it is too scary if you happen to not remember it, or haven't gotten around to studying that line yet.

I have some purely practical advice :
Since you already play the French, why not answer 1. d4 with 1. e6?
If he then plays 2. e4 you just answer 2. ... d5 and it's a French.
On any other White move (except perhaps 3. g4) you follow up with 2. f5 and play the Dutch.
I have some purely practical advice :
Since you already play the French, why not answer 1. d4 with 1. e6?
If he then plays 2. e4 you just answer 2. ... d5 and it's a French.
On any other White move (except perhaps 3. g4) you follow up with 2. f5 and play the Dutch.
This is a non Leningrad-friendly move order though, it's classical Dutch & stonewall friendly.
For the classical the literature out there is somewhat limited in terms of author breath, there's one author basically, this may not suit everyone.
The Stonewall on the other hand is a bit limiting in terms of exposure it provides, though this does imply fewer plans to learn & requires less effort. I guess the single pawn structure card is something like playing the Scandinavian Vs 1. e4, which can certainly work but may also be limiting.
I don't play the Dutch, I used to play at a club where everyone else played it though as the coach was a theoritician in the Dutch. If I were to pick a different opening for a dynamic response to d4, the Leningrad would be one of the contenders. On the other hand if I were to pick a different opening for a solid response to d4, the Stonewall wouldn't be on the cards, it could be that the OP uses a different scoresheet to select openings though and the Stonewall could be a good option.

The chessable course "Keep it simple with Black" has the Queen's Gambit Declined with black versus 1d4, and Caro Kann against 1.e4. Against an early Bg5 an d5xc4 line that can transpose to Caro Kann Panov. The basic trade off is simple and less lines to learn means less ambitious. If feel like it can slot in a more ambitious lines for example Tartakower for d5xc4.
Have always found it amusing that low rated player USCF 1300 or less can get anywhere with "minority" attacks, and subtle positional ideas in catalan, like exploting weak c6 squares. The advantages trying to exploit don't mean anything at that level of play. Anyway the 1.d4 club player loves positions were can piddle about not doing much with no risk. Two result play were they either can win or it's a draw. The course shows how can prevent that and get equal chances with all the peices on the board. For example a new idea for me was against the Botvinnik plan with Ne2, and f3 in the exchange variation playing b5 getting space on the centre, and indirect pressure on the centre.

I have some purely practical advice :
Since you already play the French, why not answer 1. d4 with 1. e6?
If he then plays 2. e4 you just answer 2. ... d5 and it's a French.
On any other White move (except perhaps 3. g4) you follow up with 2. f5 and play the Dutch.
This is actually one reason I learned to play the French. About one in a dozen will go with 2. e4. The move order avoids a lot of anti-Dutch nonsense openings like 2. Bg5 or 2. Qd3 etc.
The chessable course "Keep it simple with Black" has the Queen's Gambit Declined with black versus 1d4, and Caro Kann against 1.e4. Against an early Bg5 an d5xc4 line that can transpose to Caro Kann Panov.
The Caro and QGD with Black are my main openings, so I endorse the combo though I haven't taken that course.
Could you share the transposition line from the course between QGD and the Panov? I don't transpose one into the other & can only imagine it happening in some lines after at some point Black has player ..c5 and then ..cxd followed by a White exd.
Beyond potential transpositions between the two openings, the combo works well as there are some structural synergies eg the Carlsbad can occur in both openings ( exchange Qgd and exchange Caro ), albeit with different sides for each colour, both openings have IQP positions etc

If you want an ultra lazy defense, you can play this setup against virtually anything:
You'll have to pay attention to tactics and move order, though. And sometimes you'll need to capture with ...d5xe4 before allowing e4-e5. And sometimes you'll be wise to change your setup, depending on what white does.
Like anything in chess, thinking is still required - even with rehearsed setups.

The chessable course "Keep it simple with Black" has the Queen's Gambit Declined with black versus 1d4, and Caro Kann against 1.e4. Against an early Bg5 an d5xc4 line that can transpose to Caro Kann Panov.
The Caro and QGD with Black are my main openings, so I endorse the combo though I haven't taken that course.
Could you share the transposition line from the course between QGD and the Panov? I don't transpose one into the other & can only imagine it happening in some lines after at some point Black has player ..c5 and then ..cxd followed by a White exd.
Beyond potential transpositions between the two openings, the combo works well as there are some structural synergies eg the Carlsbad can occur in both openings ( exchange Qgd and exchange Caro ), albeit with different sides for each colour, both openings have IQP positions etc
1.d4 d5 2c4 e6 3Nc3 Nf6 4Bg5 pxp I must admit was suspicious about this line, but can't see anything wrong with it. 5e3 c5 6Bxc4 pxp 7pxp Nc6 8Nf3 from Queen's Gambit Declined.
1e4 c6 2d4 d5 3pxp pxp 4c4 Nf6 5Nc3 Nc6 6Bg5 pxp 7Bc4 e6 8Nf3 in Panov
The chessable course "Keep it simple with Black" has the Queen's Gambit Declined with black versus 1d4, and Caro Kann against 1.e4. Against an early Bg5 an d5xc4 line that can transpose to Caro Kann Panov.
The Caro and QGD with Black are my main openings, so I endorse the combo though I haven't taken that course.
Could you share the transposition line from the course between QGD and the Panov? I don't transpose one into the other & can only imagine it happening in some lines after at some point Black has player ..c5 and then ..cxd followed by a White exd.
Beyond potential transpositions between the two openings, the combo works well as there are some structural synergies eg the Carlsbad can occur in both openings ( exchange Qgd and exchange Caro ), albeit with different sides for each colour, both openings have IQP positions etc
1.d4 d5 2c4 e6 3Nc3 Nf6 4Bg5 pxp I must admit was suspicious about this line, but can't see anything wrong with it. 5e3 c5 6Bxc4 pxp 7pxp Nc6 8Nf3 from Queen's Gambit Declined.
1e4 c6 2d4 d5 3pxp pxp 4c4 Nf6 5Nc3 Nc6 6Bg5 pxp 7Bc4 e6 8Nf3 in Panov
Thanks you!, I've never played that QGD line, nor has anyone played it against me, I do play this position via the Caro Kann though. You just gave me a deviation to my QGD repertoire I can play for free, with no study needed 👍
the Panov Line ( 7. .. e6 ) is popular if one wants play a full game ahead, while 7. ..h6, after a long line, typically leads to a dead drawn endgame.
1.d4 d5 2c4 e6 3Nc3 Nf6 4Bg5 pxp I must admit was suspicious about this line, but can't see anything wrong with it.
I am also suspicious! Not sure why 5.e3 is so popular? 5.e4 must be critical, then 5...c5 is the hot move, but 5...h6 seems more consequential to me. I guess it requires analysis, if it proves at all tricky for white then I may be playing 4...dxc4 myself soon.
1.d4 d5 2c4 e6 3Nc3 Nf6 4Bg5 pxp I must admit was suspicious about this line, but can't see anything wrong with it.
I am also suspicious! Not sure why 5.e3 is so popular? 5.e4 must be critical, then 5...c5 is the hot move, but 5...h6 seems more consequential to me. I guess it requires analysis, if it proves at all tricky for white then I may be playing 4...dxc4 myself soon.
Forgetting the discussion on e4, and remaining within the e3 realm, the position is not tricky for White, it's a fairly standard IQP position. White will have an initiative, Black will try to aim for an IQP endgame, if one player understands IQP positions better than the other, they can win,

1.d4 d5 2c4 e6 3Nc3 Nf6 4Bg5 pxp I must admit was suspicious about this line, but can't see anything wrong with it.
I am also suspicious! Not sure why 5.e3 is so popular? 5.e4 must be critical, then 5...c5 is the hot move, but 5...h6 seems more consequential to me. I guess it requires analysis, if it proves at all tricky for white then I may be playing 4...dxc4 myself soon.
I was asked about the transposition to Caro Kann, not sure if 5e3 better than 5e4. The "Keep it simple" book covers 4e4 c5 and considers 5d5 most testing I think. Claims playable positions against both 5e3, and 5e4. 1.d4 club players probably won't like playing the IQP positions after 5e3, likely play something safer capturing on d4 with knight or Queen with little chance of causing problems. The Panov players would be at home with active peices. Also it is normal not liking everything about one book, and personally would play more typical Queen's Gambit declined positions with 4...Be7 heading for Tartakower.
I'm a n00b. I play chess to counter boredom. Too much study is overambitious. My aim is to learn just about enough of an opening, to get into the middlegame and wing it.
When I am white, it's all good. I call the shots. I can steer it into centre game (mostly), smith-morra gambit, french advance or caro exchange, depending on what black does. If modern, english or weird shizzle, I just abort.
When black, and 1.e4, then ...e6 all the way. Sebastien Chabal-solid.
What about 1. d4? How can I get away with learning as little as possible against 1.d4? There are too many 1.d4 players! I can't abort them all.
Any repertoire ideas? I've heard the Slav is solid, but any time I try, it gets all cluttered and tight - like banging a plus-size queen in an airplane lavatory.