How do you differentiate a co-op zombie shooter from the rest of the horde? Based on my play time with Overkill’s The Walking Dead at E3

How do you differentiate a co-op zombie shooter from the rest of the horde? Based on my play time with Overkill’s The Walking Dead at E3
20 minutes of game play at E3 2018 with Rebellion’s Strange Brigade.
Frogwares’ The Sinking City could be the game to bring the shadowy, grotesque world of H.P. Lovecraft to life in all its tentacled and sanity-shattering
Holospark’s Earthfall may fill the void of Left 4 Dead 3.
RAGE is back. It only took 7 years, but today Bethesda snuck out an announcement trailer for RAGE 2, with a promise to reveal more details