New update:
Back from the comic book convention in Aviles, all the artists I approached accepted participating in this piece.
This is what i got so far:
Participating artists:
Layout: Anthony Castrillo
Colossus: Anthony Castrillo
Wasp: inked by James Hodgkins
Nightcrawler: Jim Cheung
Changing Invisible Woman into She-Hulk: Yanick Paquette
Hulk: Dough Braithwaire (he told me not to let anyone ink it as he'll take it on next year)
Wolverine: Chris Sprouse
Captain America: inked by Guillermo Ortego
Thor: Victor Santos
Kang: Herb Trimpe
Doc Octopus: Peter Snejbjerg
I am truly happy as all artists were very nice and commented this was a great idea.
Now i'll have to wait for the next con i can attend, which will be Getxo at the end of November, let's see if i can get a few artists involved there!