Im wondering if using morph targets would be the best way to handle dialogue, the problem i can see running into is having a piece of random background dialogue and having to morph that to every character, is it possible to use the same more target on multiple meshes, or is there a more simple way to animate dialogue, I’m trying to avoid the typical “Cover all their mouths cause of disease, but really its because I don’t want to animate talking” cliche
I might be wrong but there is no easy solution for you. Morphs require exactly the same number of verts in the mesh, usually exactly the same topology. So if you`ll have copies of the same head then you might re-use it multiple time.
Depending on the complexity of the animation you want to get you might consider using joints for facial animations.