I haven't adopted any kids or did any foster care, but my parents did foster care and adopted some kids. It's easier for a straight married couple to adopt kids, because at least as far as I know, there's certain requirements you need to meet in order for the agencies to determine if you're capable of raising the kids. If you change your markings on all your documents, they'll probably still know that you were born female somehow, so depending on how things are in the future (hopefully better!) that might play a role in determining your eligibility.
As mentioned by Aleon, most trans kids are going to be older. And, older kids are usually harder to make a bond with and often have behavioral problems, so that's something that would also need to be a factor in your considerations. One of my brothers wasn't adopted until he was about 9 or so, and there was just soo much behavioral problems with him that lasted for many years, he even had to be sent to the children's psych ward for awhile (which that inpatient care and years of therapy has actually seemed to work). It's definitely manageable for people who know what they're doing, and since you've mentioned before that you're thinking of going back to school to be a gender therapist, you'll probably be all set to manage some behavioral problems since you'll need to take some basic psych courses in school. But, that's still something that shouldn't be taken too lightly.
Perhaps you could also look into international adoption as well, I hear the requirements can be easier to meet depending on which country you're adopting from.
I think you'll be a great dad no matter what kid you adopt.
