I don’t know if this would do it. But I would use a particle system that used boxes (or create my own instance) and place them on each vert. Failing that, I would put them on to fill and separate them using a distance to make it more on a grid.

On 3dsmax you can tell that particle to take the colour of the texture around it so it would pixelate the colour as well. (Box1 does this)

Anyways,
Good luck.

...Search for voxelize too… It’s not exactly that, but it may help a bit.