1. e4 e6 2. Nc3 - how should Black respond? I had White deviate from the French main line in a blitz game by playing:

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1. e4 e6 2. Nc3


Since this line is not discussed in the Wikipedia article on French defence I am thinking that Black may have better options than to simply pursue normal French development with:

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[StartPly "3"]

1. e4 e6 2. Nc3 d5


(which is what I played, it being a blitz game and all)

I was thinking maybe it's worthwhile to respond with:
2...Bb4
with the aim of a Bishop-Knight exchange and forcing White to suffer double pawns on the c-file.
Or try the non-committing: 2...Nf6 or 2...Nc6.

The chess engine XBoard / Fairy-Max 4.8Q with 50 minutes available time for Black (for 40 moves) suggested 2...Be7.

Any thoughts?
Well, let's start by looking at the position

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1.e4 e6 2.Nc3


Why does white play 2.Nc3? Because white gets two options after the standard (!) 2...d5, namely 3.d4 or 3.Nf3 as shown below

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1.e4 e6 2.Nc3 d5 3.d4 (3.Nf3)


In case black wants to aim for a French system position, I would say that 2...d5 is the best option. In case black wants to go for other types of positions, then it is possible to go for a Sicilian system with 2...c5 as well as more independent routes like 2...Bb4, 2...e5. It is also possible to go for some sort of hybrid after 2...Be7 3.Nf3 g5 4.h3 h5, as shown below. What is the objectively best move? Well, I would say that 2...c5 and 2...d5 are equally strong. While 2...Bb4 seems like an interesting option that needs a bit more research. Or just try it for fun and see where it goes!

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1.e4 e6 2.Nc3 d5 (2...c5) (2...Bb4) (2...e5 3.Nf3 Nc6 4.Bb5 Nd4) (2...Be7 3.Nf3 g5 4.h3 h5)