Games like Nightwatch
Games like Nightwatch include Firewatch, What Remains of Edith Finch, Amnesia: A Machine For Pigs, Outer Wilds, and Layers of Fear (2016). We matched them by the tags players give Nightwatch on Steam (Adventure, Atmospheric, Walking Simulator, Horror, and Story Rich): closest matches first, and among equally close ones the better-known games.
Firewatch
Shared: Adventure · Atmospheric · Walking Simulator
What Remains of Edith Finch
Shared: Atmospheric · Walking Simulator · Story Rich
Amnesia: A Machine For Pigs
Shared: Walking Simulator · Horror · Atmospheric
Outer Wilds
Shared: Adventure · Story Rich · Mystery
Layers of Fear (2016)
Shared: Atmospheric · Horror · Walking Simulator
Gone Home
Shared: Walking Simulator · Atmospheric · Story Rich
The Beginner's Guide
Shared: Walking Simulator · Atmospheric · Story Rich
The Vanishing of Ethan Carter
Shared: Atmospheric · Walking Simulator · Mystery
CARIMARA: Beneath the forlorn limbs
Shared: Adventure · Story Rich · Mystery
SOMA
Shared: Atmospheric · Horror · Story Rich
INFRA
Shared: Atmospheric · Adventure · Walking Simulator
The Park®
Shared: Horror · Walking Simulator · Atmospheric
Mouthwashing
Shared: Atmospheric · Horror · Story Rich
The Stanley Parable
Shared: Walking Simulator · Adventure · First-Person
MiSide
Shared: Story Rich · Horror · Atmospheric
Oxenfree
Shared: Atmospheric · Story Rich · Adventure
The Suicide of Rachel Foster
Shared: Walking Simulator · Atmospheric · Adventure
Little Nightmares
Shared: Atmospheric · Adventure · Horror
The Room
Shared: Atmospheric · Adventure · Mystery
Scanner Sombre
Shared: Walking Simulator · Atmospheric · Adventure
No, I'm not a Human
Shared: Horror · Atmospheric · Story Rich
DEATH STRANDING DIRECTOR'S CUT
Shared: Walking Simulator · Atmospheric · Story Rich
Poppy Playtime
Shared: Horror · First-Person · Singleplayer
Return of the Obra Dinn
Shared: Atmospheric · Mystery · Story Rich