Suppose a man dresses as a woman, and he does so so well that a casual observer couldn’t tell that he’s actually a man.1 Is this man obligated in the rules of tznius as they apply to women (ex. covering his upper arms, wearing a skirt at least knee-length, wearing a shirt with a high-enough collar, etc.) so long as he appears as one, or do they apply only to women, and since he’s not a woman he’s exempt?
I assume he’d have to keep them due to Mar’is Ayin concerns. I’m asking here if he’s fundamentally obligated in tznius because the actual halachos of tznius apply to him, not because people may think he’s ignoring the rules.
1I am not talking about a transgender, if that makes a difference. Why is he crossdressing? Maybe it’s Purim. Maybe he doesn’t care about the Torah prohibition against crossdressing. I dunno. Only address the reason if it makes a distinction in terms of the answer.