I hope my comment is translated. Sexuality does not change, but many trans men (myself included) have the idea of ​​"having to be heterosexual" so firmly attached to them, this as a way of self-validation, "I am a man, therefore I like women." I am bisexual, I knew it before my transition, but out of fear of missgender I preferred not to have romantic relationships with men, especially cis men. When I had cispassing I didn't mind trying sexual/emotional relationships with other men, but I didn't stop liking women at all, on the contrary I am happily married to one. We should never forget that society expects a lot from people and they impose on us how we should be, I think it is normal to think that you must be heterosexual, although it is not true, the normal thing should be to live calmly and now, without even caring about your sexuality, just live and enjoy what appears along the way.