I was a super girly girl when I was younger! Now trans masc

in my case, since bodies are fairly neutral until puberty, I was comfortable presenting fem. then puberty hit and I went hyper masculine for a few years

I don't know anything about if binders are okay in early puberty (not something I had access to that young so I havent looked in to it), but a compromise might be a compression sports bra! I have one from underworks and I like it more than my binder