I think there will be contests in HG/SS since on the status screen pic on Serebii it shows a button that has a ribbon on it, which means there will most likely be contests. As for the others, it'll probably be like with Gen III where you had to trade them over to evolve. Or they could just add those rocks into the games somewhere. Put the mossy rock in the Ilex Forst & put the icy rock in the Seafoam Islands. As for Nosepass & Magneton, maybe they'll make a new item that they have to hold to evolve, like the Coronet Rock in the Mystery Dungeon games.
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