My belief is human beings can and do andromorphically and gynomorphically affect our physiology. The changes are largely dependent on the age when medical treatment begins. 'Beautifying' plastic surgery and 'looksmaxxing' guys prove this can also occur in alignment within the birth sex of the individual.
These biological changes can (but not always) calm intense personal discomfort with one's sex and also (sometimes, but not always) facilitate participation in life with a bimodal sex-based form that can be agreeable. Some people desire to not have a sex-based form that sits too far in either direction.
Humans aren't clownfish. Trans people have existed in whatever cultural form they were allowed for thousands of years. People have been welcomed or shunned in society as not-male and not-female, or as-male and as-female, or many ways inbetween.
Body modification was sometimes a part of that existence. In the early 1900s, trans medicine began to more scientifically address trans health and wellbeing. Not all experiences were helpful or positive. Trans medicine has improved in the more than forty years since I've transitioned. Medicine will continue to improve.
All of what I have just said is either impossible at best or harmful at worst under sex realism.