If a cisgendered, heterosexual woman constantly says, "yes gurl" and "yas queen" even with the intention of encouraging the other person, is this cultural appropriation?
The word is cisgender.
But, potentially, yes. But it’s not just being cishet.
Meanwhile, phrasing like “yes gurl” typically is trying to mimic “sassy black woman” speech, which is appropriative and just generally racist for nonblack people to use, and white LGBT+ persons - particularly white gay men - have a bad habit of using this speech.