What to play against this Reti?
2...Nf6 was definitely wrong. 1.Nf3 Nc6 2.d4 d5 is the way to go if you play both the Chigorin and Nimzowitsch Defense, and 1.Nf3 Nc6 2.c4 e5 3.Nc3 f5 is your reversed Grand Prix

The Chigorin has good transpositions with the Queens Gambit accepted. If your opponent doesn't play g3-Bg2 and goes for an early 3.d4 then take on c4 and play next Bg4, the Janowsky variation.
In the line, you played in the tournament after 3.g3 there are many options for Black's. I don't think that suits your style to go for a closed position with a long maneuvering battle. I think the Open Catalan positions is what you are looking for...
I suggest you take on c4 and meet Qa4+ with Nbd7 and a6-b5-Rb8. The idea is to prepare Bb7 and neutralize White's Bg2. There will be a lot of semi-open files to contest and dynamic play for both sides.
The Chigorin has good transpositions with the Queens Gambit accepted. If your opponent doesn't play g3-Bg2 and goes for an early 3.d4 then take on c4 and play next Bg4, the Janowsky variation.
In the line, you played in the tournament after 3.g3 there are many options for Black's. I don't think that suits your style to go for a closed position with a long maneuvering battle. I think the Open Catalan positions is what you are looking for...
I suggest you take on c4 and meet Qa4+ with Nbd7 and a6-b5-Rb8. The idea is to prepare Bb7 and neutralize White's Bg2. There will be a lot of semi-open files to contest and dynamic play for both sides.
@Bishop_g5 your option, while theoretically good, is in my opinion not a practical repertoire choice given what the OP has said he plays. After your suggestion, white has lots of ways to take the game outside his repertoire:

I never said anything about 2...e6. The OP played 1...d5 2...Nf6 and i continued from there. Usually White's play 3.cxd5 either 3.d4 or 3.g3. These are the main continuations.
3.cxd5 Qxd5 it's a Scandinavian and the other options aiming to play a transposition to the Open Catalan is something a Chigorin player can adjust to.
I never said anything about 2...e6. The OP played 1...d5 2...Nf6 and i continued from there. Usually White's play 3.cxd5 either 3.d4 or 3.g3. These are the main continuations.
3.cxd5 Qxd5 it's a Scandinavian and the other options aiming to play a transposition to the Open Catalan is something a Chigorin player can adjust to.
That's not a Scandinavian, as white is exchanging the c-pawn for the d-pawn not the e-pawn for the d-pawn.
@Bishop_g5 I just read a good explanation for why this line is bad - in the standard Scandinavian black wants white to play Nc3 blocking the c-pawn. In this inferior line the c-pawn is already exchanged, so black is losing tempi for nothing.

@Bishop_g5 I just read a good explanation for why this line is bad - in the standard Scandinavian black wants white to play Nc3 blocking the c-pawn. In this inferior line the c-pawn is already exchanged, so black is losing tempi for nothing.
Right. Now show to us the refutation. Let me remind you that in the QGA and in many lines of the Chigorin White's play with a superior center too.
@Bishop_g5 I just read a good explanation for why this line is bad - in the standard Scandinavian black wants white to play Nc3 blocking the c-pawn. In this inferior line the c-pawn is already exchanged, so black is losing tempi for nothing.
Right. Now show to us the refutation. Let me remind you that in the QGA and in many lines of the Chigorin White's play with a superior center too.
I'm not claiming that there is a refutation, but I'm claiming that what you suggested is not as good as what I suggested in #2. Moving a piece lots of times is violating opening principles, especially if it's the queen.

What you suggest in 2# has nothing to do with mine. You propose a different first move when i take from where the OP feels comfortable against 1.Nf3.
The OP didn't mention he likes to play Open games with Black pieces. The problem with the Nimzowitch move order after 1.Nf3 Nc6 2.e4 and Black's has to pick his own way. The OP is a Scandi player so we have to assume that he will play 2...d5 but what if White's tackle's again with 2.g3 and a Reti set up? Does then the 1...Nc6 2...d5 move order fulfill what it promises? or the OP is still confused? when 3.c4 ends up again to Catalan positions?
Time to reevaluate your suggestion.
What you suggest in 2# has nothing to do with mine. You propose a different first move when i take from where the OP feels comfortable against 1.Nf3.
The OP didn't mention he likes to play Open games with Black pieces. The problem with the Nimzowitch move order after 1.Nf3 Nc6 2.e4 and Black's has to pick his own way. The OP is a Scandi player so we have to assume that he will play 2...d5 but what if White's tackle's again with 2.g3 and a Reti set up? Does then the 1...Nc6 2...d5 move order fulfill what it promises? or the OP is still confused? when 3.c4 ends up again to Catalan positions?
Time to reevaluate your suggestion.
No, the OP said he plays both the Scandinavian and the Nimzowitsch. I'm not sure why, but that's where I'm coming from. (I recommended 1.Nf3 Nc6 2.e4 d6, not 2...e5). By the way, I hope I haven't upset you by my comment? Sorry if I appeared confrontational, I'm meaning this to be a friendly discussion

I don't feel i am in a confront. It is a friendly discussion. Don't worry...
We have to assume that the OP play's the Nimzowitch to transpose to a Scandi after 2...d5. This is what i feel is consistent with his rest of repertoire. I believe he likes semi-closed positions with chances for an opposite castling.

In response to your other point, black is playing 2...e5 against 2.g3:
And after 3.e4 we are in a Glek system. Right!
In response to your other point, black is playing 2...e5 against 2.g3:
And after 3.e4 we are in a Glek system. Right!
Yes, this is a fair point. I now see the benefit of your suggestion, although I'm still not a fan of the pseudo-Scandinavian line. However, the OP didn't seem to mind playing this in his game - I certainly won't play it myself, but I don't have any intentions of playing the Nimzowitsch or the Chigorin either so it doesn't really matter

Well...You have someone who plays the Chigorin and looks for transpositions against the Reti 1.Nf3
He likes to play d5 with Black's and that is common both in Chigorin-Scandi and Nimzowitch Scandi.
We have to start with that in mind. After 1.Nf3 d5 2.c4 the most popular move is 2...c6 but is not consistent with the positions the OP likes to play. After 3.e3 and 4.Nc3 we are in a Reti Slav combat.
My idea was to give him positions he likes to play, even if they are theoretical inferior.
It is not accidentally he played 2...Nf6 against 2.c4. He doesn't look for a safe-solid position.
He wants action.