You do that already, and it’s even worse actually because everyone has an even more individual and sometimes difficult to remember thing about them you have to balance in a social situation. It’s called a name. You have to be told it, you can easily forget it, and it’s a social slight to call someone the wrong name. Right now gender expression feels uncomfortable to have to tell people because of the politisation and stigma pressed on it, but it doesn’t have to be anything different than asking for someone’s name to better address them.