I have been corrected.
I did forget about Crackdown 3. Thanks for pointing that out. (I can't wait for it)
These were the games that were announced (I took out Fable Legends since that was cancelled)
•
Gears of War 4 (Xbox One)
•Quantum Break (Xbox One & Windows 10)
•Halo Wars 2 (Xbox One & Windows 10)
•
Crackdown 3 (Xbox One)
•ReCore (Xbox One & Windows 10)
•Sea of Thieves (Xbox One & Windows 10)
•Gigantic (Xbox One & Windows 10/8/7)
•Killer Instinct: Season 3 (Xbox One & Windows 10)
•Gears of War: Ultimate Edition (Windows 10)
•Ori and the Blind Forest: Definitive Edition (Xbox One & Windows 10)
•
Cobalt (Xbox One, Xbox 360 & Steam)
Out of 11 games, 3 aren't coming to Windows 10 Store (1 is coming to Steam though). And that's what we know of so far. E3 will clue us in further if any of those changes (I doubt Cobalt changes though) and if you wanted to be more "accurate" Rise of the Tomb Raider came out this year as well.
EDIT: I did some ninja edits for Gigantic