Or someone from SamSho Sen. Kirian would be a nice add, just making him more "Raphael Sorelle" and hyping him a bit. And an actual Spaniard in SamSho would be cool(technically, Earthquake IS Spanish, since the year the game takes place in, that area was, indeed, Spain).
Also, Ashura, Yuuda or else.
Or if they want go with crossover and something not THAT samurai, Ivy, Sophitia, Nightmare, etc would be pretty epic here.
I swear there was something cool here!!