First of all, that is a difficult proposition. The easier thing to do is, you can change what is there already. The files are in Ogg Vorbis format, and something like "
Audacity" can edit the files, or allow you to record completely new ones. The files are listed by "condition", such as quiet, normal and shout, and by position of the crewmember, such as Chief or OOD, etc. I'm not 100% certain, but it looks like the numbered folders were going to be an attempt at different tonality for the voices, such as high-pitched, low-pitched, etc. That can be simulated with Audacity also, by changing a vocal files pitch.
Now, you show that your game is in "C:\Program Files (x86)\". That is not a location conducive to "modding", which is what you would be doing by changing voices. going by your game's path, I'm guessing that you have a disk version, or maybe a download version that is not restricted like a Steam version is, so you should be able to pick-up your "Ubisoft" folder and move it into a folder that you create yourself, and then Windows won't try to "protect" the game from modding. You will lose the use of any shortcuts to the game and / or Mission Editor that you might currently have, but those can be edited to the new path...
