Well fortunately most people I see making AI covers they use open source tools to do that (https://github.com/RVC-Project/Retrieval-based-Voice-Convers...)
At least that's what https://github.com/RVC-Project/Retrieval-based-Voice-Convers... links to
Realtime Voice Conversion Software using RVC : w-okada/voice-changer
Hmm not sure why the 404 when it was working just a few minutes ago.
But here is the original thread with a screenshot
https://www.reddit.com/r/OpenAI/comments/146xl6u/this_is_sca...
And the issue it posted. https://github.com/RVC-Project/Retrieval-based-Voice-Convers...