>>28798543The list is what we've seen (the top is new Pokemon/Alola and the bottom are Pokemon seen in ads/ confirmed to be returning) with riddles for upcoming Pokemon thrown in every so often (the only exceptions are the supposed starters, the strange souvenir tiki, and Marshadow which were added in without official confirmation)
The "?"s come from official info showing/telling that these specific Pokemon will have evolutions but that does not mean that the other Pokemon that don't have them will be single staged.