Games like Subnautica 2
Games like Subnautica 2 include Sons Of The Forest, Subnautica, The Forest, Subnautica: Below Zero, and Dead by Daylight. We matched them by the tags players give Subnautica 2 on Steam (Multiplayer, Survival, Horror, Underwater, and Exploration): closest matches first, and among equally close ones the better-known games.

Sons Of The Forest
Shared: Survival · Multiplayer · Open World

Subnautica
Shared: Survival · Horror · Underwater

The Forest
Shared: Survival · Horror · Open World

Subnautica: Below Zero
Shared: Survival · Underwater · Horror

Dead by Daylight
Shared: Multiplayer · Horror · Survival

Escape the Backrooms
Shared: Multiplayer · Horror · Co-op

No Man's Sky
Shared: Survival · Multiplayer · Open World

Raft
Shared: Multiplayer · Survival · Co-op

Grounded
Shared: Multiplayer · Survival · Co-op

Outlast
Shared: Horror · Survival · Multiplayer

Don't Starve Together
Shared: Survival · Multiplayer · Co-op

Backrooms: Escape Together
Shared: Multiplayer · Horror · Co-op

The Outlast Trials
Shared: Multiplayer · Horror · Co-op

Lethal Company
Shared: Horror · Co-op · Exploration

Once Human
Shared: Multiplayer · Survival · Open World

Dying Light
Shared: Horror · Survival · Survival Horror

ARK: Survival Evolved
Shared: Survival · Multiplayer · Open World

Green Hell
Shared: Survival · Multiplayer · Open World

Inside the Backrooms
Shared: Multiplayer · Horror · Survival Horror

Stranded Deep
Shared: Survival · Multiplayer · Open World

Barotrauma
Shared: Multiplayer · Survival · Co-op

R.E.P.O.
Shared: Multiplayer · Horror · Co-op

Rust
Shared: Survival · Multiplayer · Open World

Nuclear Nightmare
Shared: Horror · Multiplayer · Co-op