Nintendo:
Mario Odyssey trailer
Pokemon Stars Reveal - looks underwhelming visually
Luigi's Mansion 3 - done by Next Level Games who did the second game, coming second half of 2018
Monster Hunter port
Retro reveal new game
Microsoft:
Scorpio Scorpio Scorpio, all the details
Forza 7
Halo 6 - story trailer, lots of Scorpio mentions during this part
Crackdown 3 - gameplay and release date Q4 2017
Sea of Thieves - trailer, coming Q1 2018
genuinely don't know if MS have any first party studios that aren't working on thier big three besides Rare, so don't know what else they could have
decently sized, but not huge, 3rd party exclusive of established franchise. TR level rather than DR
Sony:
GT Sport - small trailer, launch date
Detroit - story trailer, releases this year
Days Gone - story trailer, also releases this year
Uncharted Lost Legacy - story trailer, March 2018
Sucker Punch's new game
Spiderman - gameplay trailer, coming 2018 second half
KNACK 2 STEALS THE SHOW
God of War - story trailer
Some kind of surprise colloboration between Japan Studio and another Japanese dev