Yamato isn't a tranny, she's an example of a common anime trope.
Tomboys are a thing you know, they aren't all or even mostly semi-closeted trannies...
https://tvtropes.org/pmwiki/pmwiki.php/Main/Bokukko
Btw anyone who denies the above is engaging in american colonialism, trying to imprint their own culture over Japan, and so should be deemed as racists.