Games like The Dinner
Games like The Dinner include Mouthwashing, No, I'm not a Human, Layers of Fear (2016), SOMA, and Still Wakes the Deep. We matched them by the tags players give The Dinner on Steam (Psychological Horror, Horror, Atmospheric, Walking Simulator, and First-Person): closest matches first, and among equally close ones the better-known games.

Mouthwashing
Shared: Psychological Horror · Horror · Atmospheric

No, I'm not a Human
Shared: Psychological Horror · Horror · Atmospheric

Layers of Fear (2016)
Shared: Psychological Horror · Horror · Atmospheric

SOMA
Shared: Psychological Horror · Horror · Atmospheric

Still Wakes the Deep
Shared: Psychological Horror · Horror · First-Person

Outlast
Shared: Horror · Psychological Horror · Atmospheric

MiSide
Shared: Psychological Horror · Horror · Story Rich

Summer of '58
Shared: Horror · Psychological Horror · Atmospheric

What Remains of Edith Finch
Shared: Atmospheric · Walking Simulator · Story Rich

Outlast 2
Shared: Psychological Horror · Horror · First-Person

Firewatch
Shared: Atmospheric · Walking Simulator · Story Rich

Blair Witch
Shared: Horror · Psychological Horror · First-Person

Amnesia: A Machine For Pigs
Shared: Horror · Walking Simulator · Atmospheric

Little Nightmares II
Shared: Horror · Psychological Horror · Atmospheric

Fears to Fathom - Ironbark Lookout
Shared: Psychological Horror · Horror · Atmospheric

Hellblade: Senua's Sacrifice
Shared: Atmospheric · Psychological · Story Rich

SILENT HILL 2
Shared: Psychological Horror · Horror · Atmospheric

KARMA: The Dark World
Shared: Psychological Horror · Horror · Walking Simulator

Poppy Playtime
Shared: Horror · Psychological Horror · First-Person

Fran Bow
Shared: Psychological Horror · Horror · Story Rich

Amnesia: The Dark Descent
Shared: Horror · Psychological Horror · Atmospheric

ROUTINE
Shared: Psychological Horror · Atmospheric · Horror

Visage
Shared: Psychological Horror · Horror · First-Person

The Park®
Shared: Psychological Horror · Horror · Walking Simulator