Nah they really shouldn't do it, supergroups are almost always horribly gimmicky and terrible.
But since i'm bored:
Mikko Aspa - Vocals
Hupogrammos Disciple - Guitar/Vocals
Zombie Jon Nödtveidt (wouldn't need corpse paint) - Guitar/Vocals
Bass - who the fuck cares, its black metal
Drums - Whoever did the drums on Si Monvmentum Reqvires, Circvmspice (was it a drum machine? if so, whoever programmed it will be just fine)
Would be fucked up, since thats two distinctly different guitar styles, and three distinctly different vocal styles
Oh, and granted besides Zombie Jon Nödtveidt, thats not really a supergroup since those other people aren't way huge I guess, more of a "wtf it would be awesome in a fucked up way if they played together" group.