I don't really look at Joker and and Bayonetta as "SEGA reps".
Like sure, that's what they technically are. But I really more associate them with PlatinumGames and Atlus respectively. It's the same thing with Banjo & Kazooie, they're not necessarily "Microsoft reps" despite being owned by them. People wanted them because they were long lost Nintendo/Rare characters.
I made this image recently:
Basically shows where each character in Smash originally came from, not necessarily who owns them.
I feel like the culture that shapes a character is more important than the corporation that currently owns them. It's not like we call Ryu and Ken "Capcom USA reps".