Mod support for custom portrait options and character tex?

Hi there, I'm new to modding. I was wondering if there is mod support for adding custom portrait options, like adding a new hair style, eyes, nose, etc, also for it to show in animations
I know how to replace existing ones by editing the atlas file, but is it possible to add new ones? And if it is, can somebody guide me through it?

Hi @krissm69 James here, creator of ENT, unfortunately you can't currently mod characters or add new custom portraits.