Animating veins appearance on a face


Hi everyone, apologies if it’s not the right place to ask this, not sure if I should post under zbrush or maya or…

Anyway simple question, I have a character face that I did in zbrush. My goal is to animate it inside maya using blendshape. I have a couple of angry veins on the character, how would I go about animating them ? Basically my mesh is a angry guy and the animation I want it to do is him going from neutral to a growling face. Is there a way to make the veins appear as he gets angry ?

I was thinking animating a displacement map, not sure if that would work.
Or having two face, one with veins and one without and… ?

I wasn’t really able to find anything online. Right now my mesh is still inside zbrush and the veins are a part of the face mesh.
Appreciate any guidance, cheers