What is the ruling in Islam regarding a transvestite who inclines towards wearing women's clothing, and is it permissible for him to undergo a sex-change operation if doctors confirm the presence of dormant female organs and high levels of female hormones, and is it permissible for him to pray in women's attire?

The person mentioned is male, not female or an intersex person with ambiguous genitalia, because he has a male organ and no female organ has appeared on him. The elevation of female hormones does not justify him considering himself female or imitating women. Rather, he must fear Allah and beware of imitating them, for the Messenger of Allah, peace and blessings be upon him, cursed men who imitate women. Performing a gender reassignment surgery in such a case is impermissible because it is an alteration of Allah's creation. As for the possibility of such a condition existing, specialists should be consulted about it.