Okay so not as a general rule but as a lot of people I've noticed...
It seems that transmen pass best as looking younger. Ive seen teen or young adult males pass as little boys or adolescents, Im assuming this must be from the size and rounded facial structure. Even older transmen seem to pass as younger than their age.
Whereas it seems the ladies pass when their older assuming they still have masculine traits., I've seen a lot of cis older woman have masculine traits. Something about the oncoming signs of age with wrinkles hides the facial structure, a lot of them tend to have short hair even, andsome of them have deeper voices. I'd say some of them if they weren't wearing feminine clothing I wouldve mistaken them for little old men.
As always, not everyone follows that general rule. Transwoman who have round faces or are naturally androdynous pass as their age, and most men on T catch up with muscle tone, voice, and body hair. I just thought it was a little funny thing to notice.
