Now that's a mod i didn't know i needed ! The fact that you can input any voices you want is crazy and that the most boring part is getting the .mp3, the 'modding' part is really trivial !
It's really well thought and put together, now i won't lie and say that i understood everything instantly so for anyone who want to but can't be bothered with understanding it all, here are 3 IMPORTANT TIPS :
1) AIR SDK Manager if you get 'location is invalid' in the main menu you NEED to set the location for your sdks manually (it's just above the current last version which is 51.3.2 right now)
2) Flash Develop IT DOESN'T MATTER if in the project properties menu you don't have an Installed SDK even if it tells you otherwise, i spent an uncomfortable amount of time figuring that out, just put the path to AIR SDK on the custom one underneath it and you're good, yes it says 91 warnings but IT'S OKAY
3) Here are 2 VERY useful links :
https://www.undertow.club/threads/audio-replacer-v1-extra-modding-instructions.22494/
this is a set of instruction with images on how to proceed (disco_fighter already reposted the wholde guide but the screenshots help A LOT)
https://opennsfw.carrd.co
this is a site that regroups differents voice lines and sfx from a bunch of NSFW content creators (thanks to them), there are even a few who still takes commissions so enjoy