Drifblim and Tag Switch have been revealed from SM10a GG End! The set will release in Japan on April 5th. Thanks goes to Tunu for translating!
Ability: Tag Carry
Once during your turn (before your attack), you may switch your Active TAG TEAM Pokemon with 1 of your Benched Pokemon.
[C][C][C] Spinning Attack: 70 damage.
Weakness: Darkness (x2)
Resistance: Fighting (-20)
Move 2 Energy from 1 of your Tag Team Pokemon to another 1 of your Pokemon.
You may play as many Item cards as you like during your turn (before your attack).
Creatures has chosen to hide the corner of Drifblim’s artwork because it features something they don’t want revealed yet. To me it looks like it might be Raichu and Alolan Raichu next to each other, which would mean a Raichu & Alolan Raichu-GX is in the set (hence the “Tag Carry” Ability). The colors seem to match with the two Pokemon and I think I even see part of Alolan Raichu’s tail peeking out of the blurred part. The Tag Switch Trainer revealed alongside Drifblim also features both of their types, which might be an intentional hint (although a Raichu & Alolan Raichu-GX would have to be Lightning-type if they continue with Tag Teams that are one type). But what do you think could be hidden behind the blur?