Will discuss this with the rest of the team. The trick will be to implement a solution that won't break existing content. The only one I can think of so far is to keep the UV mapping of the eyes exactly as they are, but place them on two seperate tiles. I suppose we'd also have to do the same with the brows and lashes as well.

But then we'd have to change material names for right and left eyes, lashes, and brows, so that WOULD affect existing content.

I'll see if that works.