"Game IDs summary: 24/25 - XY. 26/27 - ORAS. 28/29 - unused pentagon. 30/31 - SM. 32/33 - unused alola. 34 - mystery horohoro. 35-41 - GB VC."
This little list might be confusing, but let me explain.
In the Pokémon data, each game a Pokémon originates from is marked with a game ID, including spin-off games such as XD. In Gen VI, the Pokémon originating from Gen VI games had a blue pentagon, alluding to the Kalos' star shape. In Sun and Moon, GO Pokémon and VC Pokémon have similar markers.
In the original release of Bank, people found out there was six games that would generate the pentagon marker, two which were XY, and we later found out that the two other were ORAS. The remaining two, likely alluding to Z, were never used, but remain in the code, as you can see on top.
Similarly, for Alola eligibility, we have four IDs, two for SM, and two for futureproofing. And for VC, we have a similar thing, 4 for the VC titles, Red, Blue, Green, Yellow, and 3 for future proofing.
So what are these futureproofs? Well,
-The three remaining GB titles are obviously GSC games. Original GS were released to be compatible for the original GB, while Crystal was exclusive to Color. As 20th anniversary of GS is 2019, which will be at the tail end of Gen VII, it makes sense to futureproof their VC releases here.
-As for Alola titles, we have something fishier. Traditionally, even generations produce remakes, while odd ones don't, minus Gen III. As SM were alluding to GSC and DPPt, and because it would be their 10th anniversary, many people expected DPPt remakes to come in this generation. But remake generations generally go for a third version in addition the remakes, or in XY's case, have placeholders for such an event. But this generation only has two placeholders, meaning they are not going to follow that formula.
Similarly, since the games are supposed to be eligible with SM, that means they won't release into another console.
Or, in laymen's terms, there is not going to be a DPPt remake set or Switch game in this generation.
What we will likely have is a non-traditional third version, similar to B2/W2, for 3DS, in 2018. Or, perhaps even more likely, no future games for Gen VII.