https://superhivemarket.com/products/faceit

>Faceit is a Blender Add-on that assists you in creating complex facial expressions for arbitrary 3D characters.

>An intuitive, semi-automatic and non-destructive workflow guides you through the creation of facial shape keys that are perfectly adapted to your 3D model's topology and morphology, whether it’s a photorealistic human model or a cartoonish character. You maintain full artistic control while saving a ton of time and energy.

https://faceit-doc.readthedocs.io/en/latest/FAQ/

This is a great explanation of how FaceIt works, facial animation, shape keys, face rigs, ARKit, etc:

This addon automates Facial Animation (FACEIT Tut 1)

https://www.youtube.com/watch?v=KQ32KRYq6RA&list=PLdcL5aF8Zc...