Thanks for your answer.
I'll look if I can find a ROM who the shiny check are disable.
I know that Xerneas and Yvetal Shiny can't be played online but I'm a ShinyHunter. It's just for my collection.
Thanks !
I've just a last question,
If we can't modify the RAM who hunt Xerneas or Yveltal, why we can with a code hunt Reshiram, Zekrom and Victini in BW2 ?