A:AnswerYes, but only for storage for regular games. It will hold your Series S games, but it will not allow you to play them off of the external drive.
A:AnswerGet the one specifically for Xbox if you want to play the games off of the drive. Otherwise it will not allow you to play the Series S/X games.
A:AnswerYes, it works with Ps5, and yes. Whatever you put on it, it’ll “format” it to fit that. For example, if you only put PS4 games on there, then it’ll say “extended storage: Ps4 games” if you put everything on there, it’ll say “games and media”
Format it as extended storage, and you can put anything on there.