How to avoid picking a ladyboy? Do you look between the legs first if he/she allows you?

Pre Covid I had a most unuusal experience with a Thai WL. I couldn't pinpoint it. Somehow she didn't seem to be to a "real" girl. I walked away from the punt not fully 100% satisfied.

However come to think of it some of the girls we've met in real life are a bit unfeminine, boyish and manly too.