Yeah all the women have the same weight class (except for Dana Brooke for whatever reason. Maybe a bug or something.) So Nia Jax is in the same weight class as Alexa Bliss. It's been like that for years now which makes no sense to me since 2K wants this to be more of a simulation type game.
So the only benefit of adjusting the women's strength attribute is that in chain wrestling, if you both pick the same position, Nia would through her opponent back. Not sure how big of a difference there needs to be between their strength attribtues for that to happen. I have most of my women in the 35-55 range, Natalya and Dana at 60, Tamina at 65, and Nia at 80 or whatever the max is.