Yes, I'm doing it! But I will need to personally see the tattoo you want to cover to give you the best advice. Cover up is the last chance to get the desired tattoo, so I recommend book for a consultation firstly to discuss the possibilities in detail.
If you want to cover up the scar, it is possible not earlier than in a year. Before getting a tattoo, I advise you to visit your doctor to make sure that the scar is fully formed and will not deform in the future.