Can I apply microcement to an chipboard panel?

From the perspective of microcement, chipboard is a weaker substrate compared to MDF or HDF. It makes more sense for less stressed decorative elements where there is no risk of water, warping, or mechanical edge stress. I would not apply it blindly over the entire surface. First, verify the cohesiveness and behaviour of the substrate, because microcement is a thin finishing layer and cannot hide a poor substrate.