Is it safe to get microblading over a mole which has been shaved?

It is absolutely fine to microblade pigment over a scar, but sometimes a scar won't take up the pigment as uniformly or well as un-damaged skin will, so it's possible you will have less pigment in that area even after microblading. Overall I would expect it to look fine, and would be willing to take that slight risk. If you don't want to take that risk, consider having the mole excised and the skin sewn back together with sutures, which would give a linear scar that would be easier to microblade over (once it healed completely, of course). 

I would imagine that it would be reasonable if the eyebrow was microbladed to include the area where the mole was