The Battlefield franchise returns to World War II, some liberties aside. The biggest changes include a 64-player Grand Operations mode incorporates multiple modes across three-to-four match story, similar to Battlefield 1's Operations mode, but with some significant changes. Combines Arms provides 4-player co-op via procedurally generated missions. You'll also be able to construct and repair fortifications at specific locations. Much to the joy of folks who hated Star Wars Battlefront II's loot systems, Battlefield V will have no loot boxes or premium pass, although you can bet there will be at least some cosmetic options for forking over more money.
Overkill's The Walking Dead

November 6 | Overkill Software | Link
The Payday and Payday 2 gang know a thing or two about co-op shooters, so it’s probably a good thing that their take on The Walking Dead is a four-player FPS. Survivors will need to team up to secure a base and slice and shoot their way through the sea of zombies occupying Washington D.C. using knives, guns and special abilities. Expect to rescue other survivors, embark on missions, and work your way through your character’s skill tree and story. 
Black Mesa  

Late 2018 (currently early access) | Crowbar Collective | Link
Crowbar Collective’s recreation of the original Half Life in Source Engine has been around since 2012 and entered Early Access on Steam in 2015. Although it’s been pushed back a few times, the team expects to launch the full release at an unannounced time in 2018. Predictably, and deservingly, even the Early Access version is well-received by Half Life fans.