Aren't those three characters among the most popular in Soulcalibur
(out of the characters that weren't already in the game, of course)?
I get why they're not in the game (timeline shenanigans), but to be honest they
could have just had those characters in the base game and not had them figure into the plot. Like how Dragon Ball FighterZ has Teen Gohan, Future Trunks and Goku Black in the game, but not in the story mode (because they don't exist within the context of the time the game takes place).
I was thinking last night how I wanted Setsuka in the game, but not because I specifically wanted to play as her.
(I wanted Setsuka's playstyle for CAS).
I must have been really tired last night, because I was creating a character and bemoaning that there isn't an Ax Wielder in Soulcalibur.
Completely forgetting that Astaroth is just that.