No game that I have experienced has yet given the option to have fat characters. I would like that option but I'm not holding my breath.
Dragon's Dogma had a surpising range in character creation.
I've not played that but have watched a Youtube video on the different body types. I think 'surprising' is spot on. That seems the game to play if you want to create circus freaks! Should BG3 go for body slider, I hope they will limited them somewhat more.