Plan against pawn formation of c4, d5, e4, e3 in the Nimzowitsch defense (or similar positions in the Dunst opening) I'm a 1700-ish player who plays opening systems starting with 1.Nc3 as white and 1. ... Nc6 as black, and generally I'm pretty happy with my results.  But there's one type of setup that I struggle forming a plan against, where my opponent trades bishops on e3 (or e6) recapturing with the f-pawn.  A typical example would be:

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1.e4 Nc6 2.d4 e5 3.d5 Nce7 4.c4 Ng6 5.Nf3 Nf6 6.Nc3 Bc5 7. Be3 Bxe3 8.fxe3


What should my strategy be as black in this position?  Usually with the dark-squared bishops off the board I would try to place my knight on f4, but that's impossible with the pawn on e3.  I usually end up trying to attack the e3 pawn (with O-O, d6, c6, Ng4, Qb6 in some order), but white has no problem defending that.  Stockfish says the position is even, but I've not scored well in these type of positions and feel kind of at sea.  Any suggestions?
I play systems such as this myself. In your example White has been very unambitious and you are certainly equal at least, but you do not have the advantage that you may feel entitled to. It is worth bearing in mind that nothing is weak unless it can be attacked, and this is true of the doubled pawns here. By focusing on them I believe you are wasting your energy.

I think that the correct attitude for Black is to recognize that you have no weaknesses and an easy development and should be happy with that. Counterintuitively, Blacks strategy should revolve around ..f5, even though this allows White to dissolve his doubled Pawns and perhaps exchange his bad Bishop. This break would be normal if, for example the Pe3 were still on f2, and it is still a good idea. Black can start with ..d6 and ..0-0, then put the Nf6 somewhere and play ..f5. From your diagram play might go 8...d6 9.Bd3 0-0 10.0-0 Ng4 11.Qd2 f5 12.exf Bxf5 13.Bxf5 (13.e4 gives away the square f4 and makes the  White Bishop permanently bad.) Rxf5.  In this position I would prefer (slightly) to be Black.