Being feminine/masculine are personality traits, not a gender markers.

A cis man can be feminine, he is still no less of a cis man.

A cis woman can be masculine, she’s still a cis woman.

A trans man can be feminine, he’s still a trans man.

A trans woman can be masculine, shockingly, she’s still a trans woman.

An agender person can be feminine, they’re still agender regardless.

Having a masculine or feminine personality doesn’t dictate what gender someone is, or the validity of their gender.