I wonder if she was on male hormones. Hormones do horrible things to one’s brain chemistry and body.
I would assume that preoperative transition for a female to pseudo-male would involve increasing levels of testosterone, which would by nature increase its levels of impulsiveness and aggression. If my supposition is correct, the medical butchers prescribing and administering the testosterone may not be criminally liable for the death, but I think a good case could be made in a civil wrongful death suit by the victim's family.