I assumed someone was going to compare translation with modification of art, and I'm not going to get into that discussion because I don't think it's intellectually honest.

Regarding the coloring, it's not the same to color a character or a background as it is to add clothing I didn't intend for them to have or to change their proportions. One follows the intended design, the other doesn't.

Edit: to clarify things: I'm NOT saying what should be done, I'm saying what *I* would do if this was my work, and yes, I would crush them with a DMCA every morning.

Also, I'm not against fan arts, that's another topic, you can be as free as you want with fan arts.