Animated Material-color overlay in sequenser(How to do it?)

Ok, I’ll make this question as specific as possible.

I want to create an animated overlay texture, or material, that will colour or change the texture of a specific portion of my mesh-model.

For eg, I want to colour a specific area of my 3D map, the way that you can do it with animated shape layers in after effects.

I tried some methods, but the thing is that firstly I can’t colour a specific area and secondly I can’t freely animate an area or change its shape dynamically.

Let’s say I have a 3D map of Italy, and I want to designate a specific area with a colour, how do I do this? And HOW do I change this shape dynamically?

Thanks in advance.

So, would anyone help?
Thanks again