Yes, absolutely. Any change in the distribution of the density of mass will change the mechanics of Earth's rotation. I'm unsure if the orbit would be affected,

Yes, absolutely. Any change in the distribution of the density of mass will change the mechanics of Earth's rotation. I'm unsure if the orbit would be affected, but I assume so - since the rotational energy will be different, I expect the orbit would be too. Could we measure those changes? Not sure. The changes are probably too small for us to detect, but on the other hand, we have some pretty incredible instruments.