Fairy tales have a lot of gender swap magic and Shakespeare has more than one instance of a principal character spending a conspicuous bit of time on stage disguised as the other sex (IRL women were not yet allowed to go on stage so women's parts were played by men or boys who could pass)

In the Cyberpunk novel When Gravity Fails sex change processes have been reduced from a years-long process to hours (and now intersects with human trafficking).

All this time trans and enby folk are wishing so hard it could be so.