Today I spent about 9 hours as a medieval Lady, attending an SCA feast while wearing a circa 1400's or so gown. Interacted with lots of people, and only had one person misgender me as male. And that was a casual comment by an instructor for a class I was taking, that "he" (clearly referring to me) had a particular item that was a shared resource, and which another attendee was asking about. I might even have mis-heard her. She might have said 'she', correctly. I just let it slide. Everyone else treated me like any other lady at the event. I even got a complement on my outfit from another lady, who was trying to encourage more members to wear later-period costumes like the one I had worn!
This outfit certainly isn't the most flattering thing in my wardrobe. It flattens my chest a bit, yet does nothing to flatten my tummy! But as far as I could tell, most of the people there accepted me fully as one of the girls.
The dress and under-dress were purchased on-line, and honestly are kind of generic costuming usually sold to people heading for a renaissance faire. But the full outfit worked out quite well over all, I think.
Oh, and I wasn't the only CD/Transgender person there. The group also has a popular member who is a FtM Transgender guy, who is also a casual friend of mine. So I knew, with how well they already accepted him as a male, that they should accept me equally well as a female.