I read your comment to Janina already, Kitty, so my advice is to stay on the league president. Document misgendering is another insults by sending the league complaints in writing. Nothing over the top emotionally or anything, just a plain recitation of the facts in an email, each and every time the guy misgenders, dead names you, insults you, or whatever.

Most cis/gay men in their seventies in the US don't have any problem with trans women. That's not normal, and it's not something you should be expected to put up with.

Any league with LGBT in the name should be reminded that the T stands for something. Make sure you remind them consistently, and give them the opportunity to fix this. That's my suggestion, for what it's worth.