Talking while doing other animations?

Two solutions:

1) "Do I just use those over the other animations?" - Yes, you can. :)

"How do I do this?"

- Use "Sims4Studio"
- Then select "Override" and click on "Animation"
- Search (for example) "flatter" and check "a2a_friendly_NT_flatter_succesed_x"
- Create New
- Open this animation
- Do the animation
- Import the animation
- Click on "Save"
- Move your recently created file into mods folder.

The "Flatter" animation should be replaced.

2) If you don't need a voice during animation, then do a mouth animation.