Yeah, among populations who have access to that level of care, study after study shows good outcomes (e.g. https://www.srcd.org/sites/default/files/resources/SRCD%20SO...) – just as theory would predict. You might also be interested in another study, showing yet another way in which trans kids of X gender behave like cis kids of X gender: https://doi.org/10.1111/mono.70000.