Games like Farewell
Games like Farewell include Don't Starve Together, Terraria, Garry's Mod, Stardew Valley, and The Escapists 2. We matched them by the tags players give Farewell on Steam (Simulation, Mining, Online Co-Op, Multiplayer, and Sci-fi): closest matches first, and among equally close ones the better-known games.

Don't Starve Together
Shared: Multiplayer · Online Co-Op · Crafting

Terraria
Shared: Multiplayer · Sandbox · 2D

Garry's Mod
Shared: Multiplayer · Sandbox · Simulation

Stardew Valley
Shared: Multiplayer · Simulation · Sandbox

The Escapists 2
Shared: Multiplayer · Online Co-Op · Simulation

BeamNG.drive
Shared: Simulation · Driving · Sandbox

Keep Digging
Shared: Simulation · Mining · Online Co-Op

MudRunner
Shared: Simulation · Multiplayer · Driving

Forza Horizon 6
Shared: Simulation · Multiplayer · Driving

Car Mechanic Simulator 2018
Shared: Simulation · Multiplayer · Driving

Raft
Shared: Multiplayer · Online Co-Op · Crafting

Fisher Online
Shared: Simulation · Multiplayer · Sandbox

Tabletop Simulator
Shared: Simulation · Multiplayer · Sandbox

CarX Drift Racing Online
Shared: Simulation · Multiplayer · Sandbox

SnowRunner
Shared: Simulation · Multiplayer · Driving

Rust
Shared: Multiplayer · Crafting · Sandbox

Forza Horizon 5
Shared: Multiplayer · Simulation · Driving

Hydroneer
Shared: Mining · Multiplayer · Sandbox

Among Us
Shared: Multiplayer · Online Co-Op · 2D

Ranch Simulator: Build, Hunt, Farm
Shared: Simulation · Online Co-Op · Multiplayer

Starbound
Shared: Sandbox · Online Co-Op · Multiplayer

Elite Dangerous
Shared: Simulation · Sci-fi · Multiplayer

Farm Together
Shared: Simulation · Multiplayer · Online Co-Op

Green Hell
Shared: Online Co-Op · Multiplayer · Crafting