Back To The Drawing-Board (part two)?

A LINE against the Petrov I have long wanted to play - but never dared - is 1.e4 e5 2.Nf3 Nf6 3.Nxe5 d6 4.Nxf7!?

Position after 4.Nxf7!?

Following 4...Kxf7 White has two pawns for a knight and has prevented Black from castling.
It might be thought White should continue with 5.Bc4+, but the main line, judging by games in ChessBase's 2020 Mega database, runs 5.d4 (Short, Topalov, Morozevich and Ivanchuk have tried 5.Nc3) Be7 (5...c5 and 5...g6 are major alternatives) 6.Nc3 Re8 7.Bc4+ Be6 (7...Kf8 is also popular) 8.Bxc6+ Kxe6, at which point Komodo11.01 gives Black a slight edge but Stockfish11 reckons White has full compensation for the material deficit.
One thing you can be fairly sure about - the knight sac should not come as a surprise to a regular Petrov player as every so often it gets given an outing by a strong grandmaster. Nevertheless, it is tempting ...