I think the standard way would be using the timeline plugin and just animate with keyframes of different morph values. There are lots of morph resources with all kind of expressions for this goal, primarily the wonderful master collection of AshAuryn:
hub.virtamate.com
Usual workflow:
- search through the morphs tab which expressions you want to animate and click the checkbox to fav them
- use the timeline plugin and when adding targets, you now will see all fav morphs below the input called "geometry" (under "add storable float params").
- you now can create keyframes for that morph with a specific value and timeline will blend/animate between them
You can also use audio and play it through the HeadAudioSource of an atom to get automatic lip sync. It even works a little bit for moans etc., but you will have much better control with morphs.