Check Wikipedia. Female "circumcision" encompasses a wide variety of procedures from a minor cut in the labia or clitoral hood, through complete removal of the clitoris, labia minora and majora, and sewing shut the opening. If there's a clitoris, it will get bigger on T. If not, not. If the individual in question has a lot of scarring with an intact clitoris growth would be unpredictable, and potentially very painful.
Some of the surgeons who do gender reassignment work also work internationally to repair female genital mutilation. So if someone had one of the more extreme procedures, they might want to look into getting some reconstructive surgery first.