My mom grew up in the rural outskirts of Cincinnati and says youse. Meanwhile my dad, who grew up more inside the city, constantly made fun of her for it.

I got Cincinnati and two random places I've never even visited as my top three results, probably because my way of speaking is a super mixed bag from living in different places. Language is weird.

East coast Canadians as well.

Yeah, mainly in the northeast. I'm in the southeast and I basically only hear it from cartoon mobsters.

Surprised it's not more widespread, actually. It seems like the easiest way to pluralize "you".