Create new moods / Edit Racemenu sliders using papyrus

[Ultamix]

I'm hoping to make a mod adding custom expressions and I've tested them in game by replacing a few included in racemenu. When it comes to making them appear papyrus / scripting wise I'm stuck. I know about SetExpressionOverride and MFG console's SetPhenome but the documentation on them both doesn't include anything on creating new moods / mouths.

 

I'm looking for two solutions to help out.

A. Manipulating racemenu sliders in game using papyrus. (I'd have to follow a tutorial to add these sliders which'll have my expressions)

B. Adding a new mood that I can use with SetExpressionOverride or SetPhenome

 

I'm experienced in Papyrus and the Creation Kit but this feels out of my reach. Any help is appreciated!