Games like Radiolight
Games like Radiolight include Firewatch, What Remains of Edith Finch, The Painscreek Killings, Gone Home, and The Forgotten City. We matched them by the tags players give Radiolight on Steam (Walking Simulator, Investigation, Thriller, Exploration, and Story Rich): closest matches first, and among equally close ones the better-known games.

Firewatch
Shared: Walking Simulator · Story Rich · Mystery

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

The Painscreek Killings
Shared: Investigation · Exploration · Detective

Gone Home
Shared: Walking Simulator · Exploration · Story Rich

The Forgotten City
Shared: Exploration · Investigation · Mystery

L.A. Noire
Shared: Detective · Investigation · Story Rich

The Case of the Golden Idol
Shared: Investigation · Detective · Mystery

Unheard - Voices of Crime
Shared: Thriller · Detective · Mystery

The Vanishing of Ethan Carter
Shared: Walking Simulator · Mystery · Exploration

The Suicide of Rachel Foster
Shared: Walking Simulator · Thriller · Mystery

Amnesia: A Machine For Pigs
Shared: Walking Simulator · Story Rich · Exploration

The Operator
Shared: Investigation · Detective · Thriller

Murders on the Yangtze River
Shared: Detective · Story Rich · Exploration

Blue Prince
Shared: Investigation · Exploration · Mystery

CARIMARA: Beneath the forlorn limbs
Shared: Story Rich · Exploration · Mystery

DEATH STRANDING DIRECTOR'S CUT
Shared: Walking Simulator · Story Rich · Exploration

Sherlock Holmes: The Devil's Daughter
Shared: Story Rich · Detective · Thriller

Adios
Shared: Thriller · Walking Simulator · Mystery

Outer Wilds
Shared: Exploration · Story Rich · Mystery

This Bed We Made
Shared: Story Rich · Investigation · Mystery

Quern - Undying Thoughts
Shared: Walking Simulator · Exploration · Mystery

Fears to Fathom - Ironbark Lookout
Shared: Thriller · Exploration · Walking Simulator

Return of the Obra Dinn
Shared: Detective · Story Rich · Mystery

Heavy Rain
Shared: Story Rich · Thriller · Detective