What do you think of this variant?

If White is able to prevent Black from castling Queen-side, White wins.

If Black castles Queen-side, Black wins.

I'm kinda confused. I would think black has forced win in about 5 moves, and what does it mean to prevent black from castling?

White would win by capturing Black's Q-Rook, or if Black's King or Q-Rook move.

I think White's best strategy might be 1.e4 then Qh5 and Bc4 to threaten the f7 pawn (it's only guarded by the King, so the King would have to move if f7 pawn was captured), then after Black defends against that White could swing the Queen over to the other side of the board and attack that side.

I think it sounds like a variant that can be fun to play a few times, but then you get bored of it and pretty much never play it again. I would see it more like a fun minigame exercise and not a competitive chess variant. Nothing wrong with that though.