First of all I recommend using
Instead of the normal website, the og works too but this one has more tweening options so yeah
(Make sure the lipsync itself is a clip btw)
Step 1:
Make all the mouths you will use
Examples:
Step 2:
Convert each mouth individually into clips, choose play once instead of loop
Step 3:
Edit timeline and tween the mouth so it bounces and transitions into the next mouth, do this for each mouth
Step 4:
Copypaste the frames with the mouth needed for that specific sound a character is saying, here is a lipsync chart i got from fandom
And that’s literally it! Sorry if this wasnt clear i was gonna add more examples to make them clearer i just don’t have access to my laptop rn