Alkibiádēs on 17 June 2017
Zelda has great legs and combined with the Wii U version it will reach 10 million. Splatoon 2 will as well I think, but it will be harder (and it depends on post-launch support).
Super Mario Odyssey is a no-brainer, I'm going with a riskier prediction of 15 million copies sold (including digital of course). I hope they release DLC for it as well.
"The strong do what they can and the weak suffer what they must" - Thoukydides
