Hi,
Welcome to the ehealthforum and I am glad to help you out. It is true that microdermabrasion can help clearing acne scars.
But in case of sensitive skin it is different. Some people with sensitive skin react quite well to microdermabrasion but others simply don't. If it is done under a dermatologist's guidance, it will not have many adverse effects like redness, erythema etc. For acne scars, you can go in for laser treatment also.
I sincerely hope that helps. Take care.