I do not think you can expect a straight forward answer to this.
It is a matter of personal situation, about sincerity, how do you feel, etc. etc.
I mean, usually transgender people identify themselves with the new gender they choose.
However you chose "Female" as your gender for your IB-account, which tells me that, somehow you still identify yourself as a female.
plus the fact that you are biologically a female...so...I would say you should wear a hijab.
The question is, why are you transgender? was there a medical issue or was it more like a feeling?
You like to dress and behave like a man I assume, which is not a good thing in Islaam.
Someone who chooses to be transgender likes to show his/hers new gender to the world. He/she would dress like it, act like it as much as possible.
wearing a hijab is totally contrary to that...so transger people usually are not to be bothered with wearing a hijab.
It seems like you are trying to troll us, because your post doesn't sound very genuine to me.
About your anorexia problem...again...too little information to say you have to fast or not. Fasting is obligatory for every individual unless it forms a danger for their health somehow. So if you are dependent on medicine, pregnant orotherwise sick or weak, you shouldn't fast.
I do not know whether "starving yourself because you feel like you are too fat" (which is anorexia) is a valid genuine reason to call yourself too weak or to sick to fast.