Games like Diagnosis: No Answer
Games like Diagnosis: No Answer include Little Nightmares II, Little Nightmares, Fran Bow, Sally Face - Episode One, and SOMA. We matched them by the tags players give Diagnosis: No Answer on Steam (Puzzle, Adventure, Atmospheric, Difficult, and Psychological Horror): closest matches first, and among equally close ones the better-known games.

Little Nightmares II
Shared: Adventure · Puzzle · Atmospheric

Little Nightmares
Shared: Adventure · Atmospheric · Puzzle

Fran Bow
Shared: Puzzle · Psychological Horror · Adventure

Sally Face - Episode One
Shared: Psychological Horror · Puzzle · Adventure

SOMA
Shared: Atmospheric · Psychological Horror · Dark

Inside the Backrooms
Shared: Puzzle · Psychological Horror · Adventure

The Talos Principle
Shared: Puzzle · Philosophical · Atmospheric

LIMBO
Shared: Puzzle · Atmospheric · Adventure

Detention
Shared: Puzzle · Atmospheric · Psychological Horror

Outer Wilds
Shared: Adventure · Puzzle · Atmospheric

Stray
Shared: Adventure · Atmospheric · Puzzle

Poppy Playtime
Shared: Puzzle · Psychological Horror · Dark

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

Hellblade: Senua's Sacrifice
Shared: Atmospheric · Adventure · Psychological

The Medium
Shared: Adventure · Atmospheric · Psychological Horror

What Remains of Edith Finch
Shared: Atmospheric · Adventure · Exploration

DISTRAINT: Deluxe Edition
Shared: Psychological Horror · Adventure · Atmospheric

The Room Three
Shared: Puzzle · Adventure · Atmospheric

ROUTINE
Shared: Atmospheric · Psychological Horror · Adventure

SILENT HILL 2
Shared: Psychological Horror · Atmospheric · Psychological

INSIDE
Shared: Atmospheric · Dark · Adventure

Rusty Lake Paradise
Shared: Puzzle · Adventure · Psychological Horror

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

Endacopia
Shared: Adventure · Puzzle · Psychological Horror