This is a quick tutorial on Use Vertex Color to draw roundness and colors for objects in blender 2.9 Hope it is useful to you ...

Scientists there have created a system that allows the color of 3D-printed objects to be changed repeatedly, after they've been created.

The parts of the object that can transform have a pixelated design, and you can choose which pixels to activate (change color) or deactive (switch back to transparent) within ColorFab's interface.