Pokemon Sun and Moon has Alola starters, Johto starters on Melemele via QR codes, Unova fully evolved starters on Poni via QR codes and Kanto starters mega stones (i assume they intend for you to send them via RBY VC connection). There's also Ash-Greninja from demo but you cant evn breed it so it doesnt count really

Then the next game will/should have Hoenn starters and their mega stones, Sinnoh and Kalos starters in it. Sinnoh confirmed?