I didn't say you can't be a Christian. I hold fast to the fact that you're sinning. People chopping off body parts and/or creating artificial parts to be a different sex wasn't a thing back then. He made them male and female. Another thing: if you say you're a woman although you were born a man, and you say you are still attracted to women, and you engage in this, you say it's ok to be a lesbian. If you say you're a woman although you were born a man, and you're attracted to men, and engage in this, the fact of the matter is it's still a homosexual act.
To be accurate, I HAVE stated my sexuality in the past. And, you have no understanding of what it is, obviously.
But, more to the point that you raise. There are a few different ways to classify sexuality. A lot depends from what perspective you are working from. It is sometimes determined by genitalia. It is also sometimes determined by genes. And, it is also sometimes determined by the internal sexual organs. There are problems with all of them, since not all people have all of those elements in complete agreement. It might surprise you that most in the psychological fields determine sexuality by genitals. In that case, a MtF partnering with a man AFTER completing surgery would be classed as heterosexual, not as homosexual.
I do recognize that that troubles some people and when they understand how psychological professionals categorize transsexuals, some alter their opinions and abandon any arguments which include genitalia. However, as I already stated, there are problems with all three methods of determining sexuality. Exceptions can always be found which break the rules one uses; whether they use genitalia, genetics, or internal organs.
But, there is a 4th method to determine sexuality which most people overlook. And that method determines it on the basis of gender. Gender is an internally felt element that has no physical indicators. It also is
almost unchangeable. Using that as a basis, what might appear as homosexual to one would be heterosexual to another.
I will not make any determination on which method is absolute, since I don't see any of them as being completely perfect. But, I do recognize the validity of each of them. However, most who are in opposition to transition will refuse to acknowledge the validity of any particular one which conflicts with their mindset. What I have witnessed in the past, is opponents switching which determining method they use in their arguments against transition when it suits them. That has to be recognized as dishonest.
In the end, it makes no difference which method anyone uses to attempt to determine my own sexuality because none of them applies to my situation. And any such attempts are usually wrong.
Edited: I would be curious to know how you would classify the relationship between a transman and a transwoman. I happen to know such a couple personally.