Training someone to change the perceived gender of their own voice is a similar process to training them to speak with a new accent. I recently prototyped a gender-affirming voice therapy app for transgender women: https://own-voice-dev.netlify.app/

So now I’m curious if our two applications use the same approach under the hood! I have a detailed tech stack rundown on this page: https://own-voice-dev.netlify.app/#/info but in brief I use OpenVoice v2 to convert someone’s voice toward a differently-gendered reference voice, but leave it at only like 30%-60% transformed so it still sounds like them and not the reference. This transformed voice then becomes a practice reference for drilling.