Perfect example. I was going to say something else, but it wouldn't be the first time this has been done. Bomberman R included Master Chief, Ratchet and Clank, and Portal’s P-body for console specific versions of the game. Also, more DLC's were deployed for more charcters such as Dracula, Jephuty, and Anubs.
That wouldn't work. That would mean two different production teams doing two different games. DMC and Bayonetta both practically play the same. Only different controls and mechanics. I haven't played Bayonetta, but I have watched it, it looks like it plays similar to DMC in combat, but the QTE's are similar to something like God of War for the big boss battles.
I think I remember a playable character for a single player game such as this, but I can't seem to remember which one.