Games like The Haunted Keepsake
Games like The Haunted Keepsake include Firewatch, What Remains of Edith Finch, Five Nights at Freddy's: Security Breach, MiSide, and Layers of Fear (2016). We matched them by the tags players give The Haunted Keepsake on Steam (Adventure, Walking Simulator, 3D, First-Person, and Realistic): closest matches first, and among equally close ones the better-known games.

Firewatch
Shared: Adventure · Walking Simulator · First-Person

What Remains of Edith Finch
Shared: Walking Simulator · Adventure · First-Person

Five Nights at Freddy's: Security Breach
Shared: Horror · First-Person · Adventure

MiSide
Shared: First-Person · Horror · 3D

Layers of Fear (2016)
Shared: Walking Simulator · Horror · First-Person

Blair Witch
Shared: Adventure · Horror · First-Person

The Beginner's Guide
Shared: Walking Simulator · First-Person · Story Rich

The Beast Inside
Shared: Adventure · First-Person · Horror

Kona
Shared: Adventure · First-Person · Walking Simulator

The Death | Thần Trùng
Shared: Adventure · Horror · Realistic

Welcome to Kowloon
Shared: Adventure · Walking Simulator · Horror

Resident Evil Requiem
Shared: Horror · First-Person · Adventure

Amnesia: A Machine For Pigs
Shared: Walking Simulator · Horror · First-Person

Kingdom Come: Deliverance II
Shared: Adventure · First-Person · Realistic

Ready or Not
Shared: Realistic · First-Person · Horror

The Painscreek Killings
Shared: Investigation · Walking Simulator · Horror

Bendy and the Dark Revival
Shared: First-Person · Adventure · Horror

Killer Frequency
Shared: Adventure · Horror · Walking Simulator

Riven
Shared: Adventure · First-Person · 3D

Still Wakes the Deep
Shared: Horror · Walking Simulator · First-Person

The Stanley Parable
Shared: Walking Simulator · First-Person · Adventure

Prognostic
Shared: Adventure · Horror · First-Person

Before Your Eyes
Shared: First-Person · Walking Simulator · Adventure

Red Dead Redemption 2
Shared: Adventure · Story Rich · Realistic