Warhammer 40,000: Darktide was announced during Microsoft Xbox Series X showcase event. It's due out at some point in 2021.
Warhammer 40,000: Darktide is from Fatshark, the developer of the brilliant Warhammer: End Times - Vermintide series of first-person co-op games.
Similarly, Warhammer 40,000: Darktide is a four-player co-op game set in hive Tertium. Here's the official blurb:
"Go deep into the hive city and face hordes of enemies you have only seen in your nightmares. Players will not be able to hide behind lethal ranged weapons, they'll need to combine both FPS and melee skills as they get up close and personal in visceral clashes between Imperium and Chaos factions. Warhammer 40,000: Darktide will bring everything you have come to expect from the developers of the multimillion selling award-winning Warhammer: Vermintide franchise."
And here's the trailer: