While this may simply be something else, I saw a video on youtube where someone was having the PC voice out his lines, with lypsynch, apparently it was supposedly for a fan-made Kotor movie. I was quite interested in how this person would have accomplished it.
Regardless, this kind of mod has been thought of before but not only is it very time-consuming, what is required to make it possible would be tough.
However, I would like to point out that cloning and NPC of the PC is sort of a good idea, when instead you convert the PC into an NPC for a specific amount of time in which he/she speaks his/her lines.
If this project is to be done, I would like it if they made the PC into less of a drone for the Jedi as an LS character.