His mark is, for some reason, a lot more sensitive and a lot darker than the others.
Also, his attitude doesn't help it.
I was able to seal Zanji's and switch it around using a complicated series of sharingan/chakra/sealing techniques. Sasuke08's curse mark is more powerful (in a bad way) and can't be as easily turned into a good thing as Zanji's was.
To do that I'd need to combine the curse mark with a powerful seal that I'd have to create and then combine that with another combination of the not yet invented seal and the mirror heaven earth change technique.
I'd have to invent a new seal, basically, and find an effective way of combining it with the curse mark and then combining another with the mirror heaven earth change.