Pussycats would have been way too easy. Since their deckbuilding wouldn't be changed at all.
As for Saho.. Well, since normal transpeople are more commonly referred as the gender they identify as, Jackie Cr would have probably been allowed. Whereas Saho's shifting between the opposites of gender spectrum based on wetness, s/he would be referred to as whichever s/he happens to be at the time. So there could have been a chance of male Saho passing through for the all-female event and he was left out?
Sure, deckbuilding would have been easy with cats, but the whole theme of Girl Power and no boys allowed practically paints a neon sign on them.
Jungo, sents, junta and Skeelz are pretty much equal opportunity. Do any of the allowed girls even care about girl power in particluar or bias against guys in general?
Still, guess it makes it a bit different. Wouldn't mind it if they made a T1 event oneday though...