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I made a chart. All are gifts or interactable, with the exception of Staraptor, Roserade, Floatzel, Weavile, Froslass and Snorlax; the first five are often seen in Sinnoh teams (such as the Rival's) and I put Snorlax in due to Munchlax's status in DPPt.
I admit the distinction is slightly arbitrary; I'm just going by which Pokémon receive the most attention from Gamefreak.
Also, Giratina would probably be Origin Forme, but I don't have that sprite.