I can't believe you're trying this hard to pretend that a guy disguised as a woman isn't a staple of media. I can even tell you how like 90% of them go.

Dude is in disguise, somehow he has to go to the locker room, usually only to maintain his disguise or optionally to steal some important plot item out of a locker and he may even have to change clothes while trying not to get a massive boner that pokes through his towel. Optionally the girl he likes attempts to have a conversation where she either talks about her feelings about him as a man or complains that there are no good men. Also there is a high probability that there will be a request to apply soap or lotion to another woman, someone will ask the protagonist a question about their titties or someone will request a massage. If this is japanese media our hero will for some reason get a nosebleed at this point.

There is a 5% chance that our friend will be discovered and if this is an 80s or 70s sex comedy he will get paddled by the dean or principal over a desk while making exaggerated pain faces. The dean will be a fat chick or a guy with a goofy moustache. He may get discovered and try to run out the door with a gang of angry naked women in hot pursuit but will plow straight into an extremely buff female gym instructor at the door. She will wear a sleeveless shirt to show off her biceps she will invariably have a chrome whistle on a chain around her neck. She will beat his ass and assign him detention. Later on he will carry his love interest's books while walking funny from his paddling and she will say "Why were you guys in there anyhow" and then he will reveal that he has magic powers or that one of the girls has accidentally taken his science experiment in her shampoo bottle and the fate of humanity depended on getting it back.

The porny-ness of these scenes is typically somewhere between sideboob comedy and a full blown porn.

Please anyone who grew up watching "USA up all night" tell me this didn't happen in at least half of all the featured movies. That said I think that perverts already go in the womens room and get arrested. Perverts already go in the mens room and get arrested.

Also as it is little boys aren't getting molested by strangers in the men's bathroom so even though there is sure to be someone attempting to use this as a perv loophole it probably represents very little actual danger to the public.