Meghdad Asadi Shows a Common and Easy Way to do Character Facial Expressions in Ae.
Meghdad Asadi extends his character rigging basics in After Effects to setting up simple facial expressions. Previously, a tutorial showing a basic overview of setting up bones and IK/FK with the free DUIK tools. The companion tutorial to that is how to set up the smaller details of facial expressions.
Asadi walks through how to prepare your content and assets first and then covers an easy way to create a facial expression system in After Effects. The technique uses an almost “standard” approach of making use of the time remapping feature in After Effects to call the correct face shapes.
A more complicated setup is how Dave Legion used a custom slider interface to control the expressions. The system still used time remapping, just with much more stuff on top of it. Check out that tutorial here.