it's tough, so much in society still confirms directly or indirectly that women have a shelf life and limited value. Has she read any of the Rebel Girls stories? Taking the focus off of the physical appearance and putting it onto other achievements might help.
I put a lot of thought into this because my own child is trans so she deals with some level of body dysmorphia. I want to make her feel comfortable in her own skin no matter which path she chooses in life. As far as I can tell it's working because he body doesn't seem to cause her distress anymore, puberty may change that though