[@Tulpa] Firstly, I've never been in an RP with a transgender character so I will admit everything I write is purely hypothetical/conjecture.  I seriously doubt that any problem would arise solely because of a trans character.  A good roleplayer is a good roleplayer, no matter their gender/sexuality/race/ect.

Isn't the GM essentially god however?  So doesn't that mean they can choose the rules?  If a GM said no cisgender character I would obey that rule.  Similar to no romance ect.  Have you ever actually been kicked out because of your character is trans?

You say that being transgender is an important part of your identity, but that implies that you aren't completely the same mentally as someone who was cisgender that you identify as.  Is that what I am supposed to understand?  So therefore, given the option (IRL) to be born as the same sex and gender you wouldn't take it, sense being transgender in as of itself is your identity?  If your answer to that is yes then in a fantasy world ideally you would be trans.  But if your answer is no then you would ideally be cis of your gender.

Lastly, do you consider it discriminatory if a character who would be attracted to your gender is not because of your sex?  In a perfectly non-discriminitaory fantasy world, what would you want?

Thanks for your patience.