Anti-French/Necchi Variation - Is it any good?
It's actually good. I used to use it then I switched to 3.Nc3 ( I didn't know Winawer Theory then I learned. )
Its like an inferior version of the Tarrasch; black can play ...c5 easily and also can play ...de and then ...Nf6 with tempo. Too many routes to easy equality. As white, you shouldn't let your opponent off the hook so easily. 3.Nc3 is the way to make black sweat.
Well, I guess how one defines "weak" in regards to chess after all it can be a such a subjective term based upon ones playing strength and the dogma that one subscribes too.
As to:
>Black can play c5 easily<
The same could be said for most variations of the French.
and
>Can play ...de and then ...Nf6 with tempo.<
Well, yes. The thing is though that tempo does buy you a big bishop on the a8 to h1 diagonal (after it drops back to f3).
Finally
>It doesn't see play because it is weak"
It does see play, it is in the repertoire of G.M Vladimir Onischuk.
Back to your original question, is it any good? All I can say is, it is better than some and worse than others. My preference for the French is Kupreichik's Be3 in the Advance variation.
HTH
Any good? Probably not. The Advance Variation is probably better. In your variation, the B gets attacked with tempo and must retreat because it can't achieve anything on e4.
The reason why I like it is because it takes the typical French player into uncomfortable waters. The position after, for example, 3...dxe4 4. Bxe4 Nf6 5. Bf3 c5 6. Ne2 Nc6 7. Be3 Qb6 is very open, and a far cry from the typical semi-closed positions of the advanced or Tarrasch or Winawer variations which the 1...e6 player is likely highly familiar with.
Also, if my opponent plays 3...c5 I follow up with 4. exd5 exd5 5. dxc5 Bxc5 and now I have an isolated queen pawn to target.
I think it's unduly underestimated. Maybe it's not theoretically quite as good as other possible options in the French, but it's certainly not weak.