Games like The Mansion
Games like The Mansion include Outer Wilds, The Room, The Room 4: Old Sins, Firewatch, and The Room Three. We matched them by the tags players give The Mansion on Steam (Adventure, Casual, Indie, Puzzle, and Story Rich): closest matches first, and among equally close ones the better-known games.

Outer Wilds
Shared: Adventure · Exploration · Story Rich

The Room
Shared: Puzzle · Adventure · Point & Click

The Room 4: Old Sins
Shared: Adventure · Puzzle · Point & Click

Firewatch
Shared: Adventure · Story Rich · Indie

The Room Three
Shared: Adventure · Puzzle · Indie

Sally Face - Episode One
Shared: Indie · Story Rich · Adventure

What Remains of Edith Finch
Shared: Story Rich · Adventure · Exploration

The Room Two
Shared: Puzzle · Adventure · Point & Click

Amanda the Adventurer
Shared: Puzzle · First-Person · Adventure

There Is No Game: Wrong Dimension
Shared: Indie · Adventure · Puzzle

Call of the Sea
Shared: Adventure · Puzzle · Story Rich

Boxes: Lost Fragments
Shared: Adventure · Puzzle · Casual

Fran Bow
Shared: Adventure · Puzzle · Story Rich

Myst
Shared: Adventure · Puzzle · Exploration

Chants of Sennaar
Shared: Adventure · Puzzle · Indie

Blue Prince
Shared: Puzzle · Exploration · Story Rich

Riven
Shared: Adventure · Puzzle · Exploration

Gorogoa
Shared: Puzzle · Indie · Casual

Rusty Lake Paradise
Shared: Adventure · Puzzle · Indie

Servant of the Lake
Shared: Adventure · Puzzle · Indie

The House of Da Vinci
Shared: Puzzle · Adventure · Point & Click

Detention
Shared: Indie · Adventure · Puzzle

The Death | Thần Trùng
Shared: Adventure · Indie · Puzzle

Obduction
Shared: Adventure · Puzzle · Indie