Games like Baryum
Games like Baryum include Elite Dangerous, No Man's Sky, X4: Foundations, Starfield, and Kerbal Space Program. We matched them by the tags players give Baryum on Steam (Space Sim, Simulation, Space, Open World, and Exploration): closest matches first, and among equally close ones the better-known games.

Elite Dangerous
Shared: Space Sim · Space · Open World

No Man's Sky
Shared: Space · Open World · Exploration

X4: Foundations
Shared: Simulation · Space · Space Sim

Starfield
Shared: Space · Open World · Exploration

Kerbal Space Program
Shared: Simulation · Space · Space Sim

SpaceEngine
Shared: Open World · Space Sim · Space

PULSAR: Lost Colony
Shared: Space Sim · Simulation · Open World

Universe Sandbox
Shared: Simulation · Space Sim · Space

Outer Wilds
Shared: Space · Exploration · Open World

EVE Online
Shared: Space Sim · Open World · Exploration

Kerbal Space Program 2
Shared: Space · Exploration · Simulation

Dyson Sphere Program
Shared: Space · Simulation · Open World

Empyrion - Galactic Survival
Shared: Simulation · Space · Space Sim

Avorion
Shared: Space Sim · Exploration · Space

X Rebirth
Shared: Simulation · Space · Space Sim

Rebel Galaxy
Shared: Space · Open World · Sci-fi

Euro Truck Simulator 2
Shared: Simulation · Open World · Exploration

Starcom: Unknown Space
Shared: Space · Space Sim · Open World

The Long Dark
Shared: Open World · Exploration · Simulation

Spaceflight Simulator
Shared: Space Sim · Space · Simulation

Space Engineers
Shared: Space · Simulation · Open World

Hardspace: Shipbreaker
Shared: Space · Simulation · Sci-fi

Endless Sky
Shared: Space · Open World · Simulation

American Truck Simulator
Shared: Simulation · Open World · Exploration