No, I dress very feminine and sometimes play girls in games as well, but I’m not a girl, I’m a transmasc. I know for sure I’m trans also, there isn’t a shred of doubt in my mind. I utterly hate so many things about being AFAB, especially my periods (those cause crippling dysphoria for me 😔 ).

It’s entirely possible, but that’s something for every individual to find out for themselves. You can be a confidently cis dude and find it enjoyable to have a female avatar, correlation == causation.