Sleeping Dogs is fucking fantastic. I haven't played it in a while, but it was one of those free Xbox Gold games a while back so I've got the free definitive edition somewhere on my Xbox account. I'll have to get back into that after I finish my wide backlog of other single player games that I need to play, but haven't been able to make the time to finish because life is a cunt and keeps getting in the way of me having fun.
My game time has been very limited, so I've mostly been getting into games with a multiplayer component so I can play with this group of friends I've got here and lately we've been very into State of Decay 2. I never played the first one, but I'm really into the second one. It's a cool open world zombie survival game - you have a small community after you get through the intro and your goal is to make it through each day and survive. Each day gets tougher and tougher and there's other NPC communities that might ask you for help (or demand you give them resources); if you don't give into demands/help people out then you've got a weird situation where not only are there hostile zombies out to kill you. But also hostile arseholes who are either too needy and expected you to drop your own survival to help them; or a bunch of greedy bastards who want to take your hard earned shit. So there's sometimes fuckers with guns you've got to worry about too.
But if you help people, you can rescue other survivors and have them be a part of your community. And there's a semi-RPG element; the characters have their own personality traits, they get better the more they do certain things (like the more zombies you beat to death, the better you become at fighting) and once you max out a skill you upgrade it and it's sort of like a very simple skill tree where you've got a choice between what you specialise in. Other than that, you collect resources, build up your community and your base, murder zombies, etc... If you've got a survivor in your community who's a total cunt, they'll start fights with people and decrease moral and you can exile them. Or more fun than exiling them is sending them out on a suicide mission.
If any of your survivors die, they're permanently dead and you can't revive them. So you've got to be pretty careful. When you're doing co-op, you just play on your friend's community... but you can access all of your survivors from your community to help them out. You get rewards for playing properly and helping their community once you log back into your game - so as to encourage actual co-op. And shit can go from looking total fine to very fucking hectic pretty quickly.
It's a quality co-op game and I highly recommend the fuck out of it.