Once on a flight I sat next to a lovely young woman who turned out to be named Jason. I still don't quite believe it.
Dressing up like the opposite sex is transvestism, not the same thing as being neither or both male and female.
It did happen to me years ago. I went into a store to apply for a job. The guy at the desk said the manager was "down that aisle". I saw a woman with long hair in that aisle, so I said "Excuse me, ma'am...?" And he turned around. I didn't get the job.