Metamorphmagi being dead
I only have one question I think:
Do you think that if your dead, and your a metamorphmagus you could still change your appearance?
Are you talking about the physical self or some sort of afterlife?
If it's the afterlife, I think you can do whatever you want. If you no longer have a body, I daresay you can look like whatever you want, regardless of whether you're a metamorphmagus or not.
If it's a question of the physical body after it's expired, I'd say no. If you're dead, you're dead. Just like how you can't move your hand or blink or anything like that, I don't think your appearance can change either (apart from the decomposing, of course). As far as we know, regular dead wizards' bodies can't to magic, so I find it highly implausible that that of a metamorphmagus could.
Of course, if they become a ghost it would be a slightly different matter, as ghosts seem appear the way they did when they were alive (or when they died). You could probably get away with having the ghost of a metamorphmagus change their appearance, although I'm not quite sure it would actually work... Hard to get my head around these things, as I don't know any ghosts.
I do believe, however, that when a metamorphmagus dies, if they were not in their original form they will automatically revert to the way they really look. Most likely the same with animagi.
Hope I could help.
I think that when you die you would change back into your actual appearance, but I don't think that it is voluntary. If you mean they are a ghost or in the afterlife then I would think they still can.
It was the afterlife I was talking about. I was that they could, but I wasn't sure.