Jaw Left/Jaw Right and Jaw Forward

Are you familiar with making face tracking shapes?

If you are not familiar with creating shapes yourself, the Unified Expressions documentation on VRCFaceTracking can be a good reference.

These shapes allow you to move the jaw, but by default, this includes the upper side of the mouth in order to create smoother deformations on anime-style avatars.

If your avatar has a very large jaw as it is the case with the face structure of some furry avatars, you can check the “Jaw … Puller Only Lower” checkbox so that the Jaw puller will only change the lower part of the mouth divider.