There is an upcoming book that discusses drugs that could alter sexual orientation. It's called Love Drugs: The Chemical Future of Our Relationships by Brian Earp and Julian Savulescu.
Possible procedures to alter sexual attraction could be neuropharmacology but also brain surgery, deep brain stimulation, genetic/epigenetic engineering. It's about changing sexuality to whatever the person wants. It has been discussed by biohackers elsewhere: https://www.reddit.com/r/Biohackers/comments/aawykp/modifying_sexual_orientation/