. This generated a "Slider Control" based on the volume, which they then linked to the mouth’s scale or a time-remap expression to make the character "react" to the sound. Slider Controllers
To make it look natural, add subtle random movements (wiggle expression) to the jaw or head, even when the mouth is closed. Download Free Auto Lip Sync After Effects Plugins
Disclaimer: Free plugins may have limited features compared to paid alternatives. Always test with a short audio clip first. If you can tell me: Are you animating or photos ? Download Free Auto Lip Sync After Effects Plugins