A man can legally become a woman when he completes a sex change. The best way I can describe it is transgender people have been sent to prison and made to live with men because they are legally a man because they have not completed their transformation. But those who have become a woman legally are housed with other women. The state and/or federal courts have final say though. And it wouldn't be up to Dana White or any other promoter. It'd be up to the athletic commission in that particular state.