Games like Goodnight, Sweetie
Games like Goodnight, Sweetie include Poppy Playtime, Little Nightmares, MiSide, Little Nightmares II, and Firework. We matched them by the tags players give Goodnight, Sweetie on Steam (Horror, Psychological Horror, Psychological, Mystery, and Puzzle): closest matches first, and among equally close ones the better-known games.

Poppy Playtime
Shared: Horror · Puzzle · Psychological Horror

Little Nightmares
Shared: Horror · Puzzle · Puzzle Platformer

MiSide
Shared: Psychological Horror · Horror · First-Person

Little Nightmares II
Shared: Horror · Puzzle · Psychological Horror

Firework
Shared: Horror · Puzzle · Psychological Horror

Portal 2
Shared: Puzzle · Platformer · Puzzle Platformer

Garten of Banban
Shared: Horror · Psychological Horror · Puzzle

LIMBO
Shared: Puzzle · Puzzle Platformer · Platformer

Inside the Backrooms
Shared: Horror · Psychological Horror · Puzzle

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

The Room Two
Shared: Mystery · Puzzle · Horror

Mouthwashing
Shared: Horror · Psychological Horror · Psychological

Buckshot Roulette
Shared: Horror · Psychological · First-Person

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

SILENT HILL 2
Shared: Horror · Psychological Horror · Psychological

ANIMAL WELL
Shared: Puzzle · Horror · Platformer

Viewfinder
Shared: Puzzle · Puzzle Platformer · Psychological

Fran Bow
Shared: Psychological Horror · Horror · Puzzle

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

Portal
Shared: Puzzle · Puzzle Platformer · 3D Platformer

Bendy and the Ink Machine
Shared: Horror · Puzzle · First-Person

Superliminal
Shared: Puzzle · Psychological · Psychological Horror

Garten of Banban 2
Shared: Horror · Psychological Horror · Puzzle

Outer Wilds
Shared: Mystery · Puzzle · Horror