In FragPunk, crossplay availability depends on the game mode you are playing:
We in CrossWatch think that this is fair, you all may know the situation with Warzone, where cross-play was available by default for all platforms, and as a console player, who maybe plays on console to avoid cheaters, it may be a reason to quit the game, but that's good FragPunk do not repeat others mistake.
Because games with cross-play can't rely on platform specific account storage like Steam or PSN, they need store user data by themselves, and FragPunk is not an exception, and you will have to create an account for this game to be able to play with cross-play
On console, you will have an aim assist, but in cross-play lobbies with PC, your aim assist will be reduced. As far as we understand the cross-play in FragPunk will be similar to one we have in Apex Legends, that means if you are playing on PC you will never be able to get into console lobbies, but if you are on console, and you create a squad with your PC friend, you will play only in PC.