Well, I'm a woman and I've known a few men who were very convincing as women. So convincing I didn't realize they were men until they told me. That was unusual even at the time, a long time ago, when what we then called transsexual men (vs. crossdressing men) for the most part wanted very much to pass as women, without a public fuss or any issues with restrooms. Since women's restrooms don't have urinals or open toilet stalls the only barrier to entry is one of appearance. Which is sort of ironic, as more masculine-appearing women routinely get challenged in public restrooms. As I well remember from my short-haired days.