As an autistic person, I typically use "they" as a standard pronoun when referring to the generic word of "people" in the third person (sometimes I'll say "he or she" rather than "they"). I'd be inclined to use "they" if I'm uncertain about someone's gender identity. If I accidentally misgender someone (in person), I apologize for it and make a mental note of their correct gender identity. I don't mess around with "zhe" or other bizarre variations beyond she/he/they.