The laws are so different between place and have, as ever, not caught up with public opinion.
Where I am the police verbally state very clearly to go to the toilet of your appearance. If you are presenting as female go to the ladies loo. If you present as male go to the male loo. If you are a MtF who doesn't present very well have a consider. If you are an FtM who doesn't present well consider. We have personal choices and need to think through them.
The law may be (is) completely the opposite, 'male' sex go to male toilets, 'female' sex go to female toilets. It is an offense to go to the 'wrong' sex toilets. Guess what? The great legislators forgot to look up the difference between sexuality and gender.

The law is based on sexuality and not gender.
So I use the ladies quite legally. And no politician wants to go back and 'correct' the mistake. But you do have to be careful, but we have to be careful about lots
Cindy