1. ...e6 repertoire?

I like to play the French defense against e4.  Against d4 I've also been playing ...e6, and that often tranposes into the French because I see 2. e4 in response often enough and I just reply 2. ...d5.  But 2. c4 is also common, and again I reply d5 and then we're in the QG, which I'm not as familiar with.

So I was wondering if there's such a thing as building a repertoire around 1. ...e6 no matter what White starts with?  And how many rabbit holes does that really lead to?  I want to keep things simple and not learn a hundred openings, while I study general tactics, strategy and endgames.

I said "no matter what White does."  I would have hoped that the hyberbole was obvious.  However, playing e6 against "many" White moves is different, and doesn't necessarily sound ridiculous at all.  To play e6 against "many" White moves does not imply playing it against g4, for example.  I personally have never seen 1. g4 so I think I'm safe in planning a little preparation against e4 and d4 which is 90% of what I see, and there are probably a few other white starts for which ...e6 is appropriate enough, as well.

I'm going to assume you're a much better chess player than I, but since you're posting mostly non sequiturs so far, I haven't learned anything yet.  I already implied your answer in my original question (1. e4 e6, 2. c4 d5 does not a French Defense make.  Obviously.  I hoped.)

You rephrased my question fairly well.  Now, if anyone has any suggestions?

True.  I have been trying e6 in a lot of my OTB games against d4. They often do reply with c4 and then my usual line goes as follows, in order to transpose into the Triangle variation

I just came across this, but it seems aimed at 1800+, so I'm looking for any suggestions closer to my level.

https://www.chess.com/forum/view/chess-equipment/a-rock-solid-chess-opening-repertoire-for-black-by-viacheslav-eingorn

OK.

Hmm, interesting, never heard of it.  At some point in QG I end up trying to play c7-c5, and it's never worked out all that well for some reason.

As mentioned in the OP, it can occur transpositionally after 1. d4 e6, e4 d5.  I'm not saying it's forced, I'm just saying it happens in my games sometimes.

You could try the English Defence after 1 d4 e6

https://en.wikipedia.org/wiki/English_Defence

They say the best thing to pair the French with is the KID (closed positions with pawn chains and stuff). Incidentally, if you're inclined to start with 1...e6 to avoid various d-pawn sidelines and whatnot, you can play basically any set-up against 1 d4 involving the move ...e6. As for specific advice regarding which of the many available options you should choose, we'd probably need more detail regarding your playing strength, style, maybe even what your repertoire within the French consists of, and so forth. Otherwise, we're sort of shooting in the dark at what you'd like 

Really like the Eingorn book you found, but maybe some of the suggestions against 1.d4 , involving 1...e6 2c4 Bb4ch 3Nc3 c5 or b6, are positionally too complicated for a beginner standard player. Purdy wrote one suggesting the QGD instead, which is maybe more appripiate. The book is old from the 1950's I think.

As black, you could use 1.d4 e6 to transpose into the Classical variation of the Dutch Defense after 2.c4 f5.

Perhaps it would be of interest to look at A Rock-Solid Chess Opening Repertoire for Black by Viacheslav Eingorn (2012).

https://web.archive.org/web/20140627113531/http://www.chesscafe.com/text/hansen156.pdf

I used to do the same thing French against e4 and the classical dutch against d4.The advantage of 1.e6 in the dutch is that it avoid's all the annoying gambits and the Anti-dutch.The disadvantage is that you cannot really play the lenigrad dutch if you start with 1 e6.

I'm playing 1...f5, most of the time, and for fun only.

Well, I just played my first chess.com game against a person.  I'm not a premium member so I guess I can't show it to you.  Here are the moves.  I'm learning a d4 repertoire like Colle, Torre, etc.  In this game Black left it open for a Stonewall so I did.  This is the sort of style I like to play when I can.  I  have some time to plan without getting lost in decision trees early.  10 minute game.

I don't understand how to post here, I added comments, but it messed up my post.  21. was a misclick, was supposed to be Qd3.  17. I just hung the pawn, typical mistake.  24. I had something planned but I miscalculated.

It started me with a 1200 rating by default I guess, and it bumped to 1347 after 1 game???  Anyway, that's typical of how I play.  I see some things and miss some things.

I have been working on a repertoire lately that could enlighten your issue.

Against 1. e4 I go for the French.

Against 1. d4 I go for the Tarrasch Defence, and pretty much Tarraschesque defence against most of Whites different openings. 1. Nf3, 1. c4, etc.

So I could see how especially for me, playing 1... e6 no matter if White opens Kings pawn or Queens pawn could probably work out well. Because if they open queens pawn and I reply with 1... e6, it could easily transpose right into a French defence. But otherwise I will end up in the Tarrasch defence. Or something in that territory that I play for pretty much all queens pawn games, with slight adjustments if they play something like the London or Colle.

For me the Fench and Tarrasch are similar in the very begining, same pawn structure, c5 pawn break idea, Bc8 is locked in. Although the games are different, Tarrasch opens up and usually leaves you with an Isolated Pawn. 

So maybe its not the answer for you, but certainly with what I have been working lately I could EASILY handle playing 1...e6 regardless is king/queens pawn game.