If you transfer from Gen IV you can get the trio but you can't bring along items. So that's the main reason why you get those Orbs.
Because in the Pokemon dream radar if you have diamond, pearl, or platinum you can get Dialga, Palkia, or Giratina. The orbs help them, but you probably know that already.
I think this already answering by the post event Shiny Creation Trio. There are Shiny Dialga/Palkia/Giratina. So good if I can get one too.