It would require a lot of VFX work - I remember someone doing a really cool VFX test to turn Rey’s outfit black, which was a 1000% improvement, but the AI software couldn’t detect the edges perfectly. Changing a person’s skin to blue would be even more difficult for an AI, and I think you’d have to manually rotoscope it in most shots. That’s a staggering amount of work; just look at the “crackling saber” VFX from the Ascendant edit thread.

It’s possible, but it would take a huge amount of work, besides which - do you really want Pryde’s character in the movie to be Thrawn? He doesn’t really gel with Thrawn in the rest of SW media personality wise.