Personally I don’t see any harm with this. Puberty is delayed, there aren’t any long term side effects, and it can be restarted when the child is ready. Additionally being able to decide on these type of permanent and very significant changes require a lot of thought that a young child is not capable of. Better to delay puberty, work through any mental health issues, and then do transition surgery if thats whats decided on later or to go through puberty to remain their current gender.