Games like Xenoform
Games like Xenoform include Elite Dangerous, SpaceEngine, Kerbal Space Program, War Thunder, and X Rebirth. We matched them by the tags players give Xenoform on Steam (Action, Simulation, Space Sim, Third Person, and 3D): closest matches first, and among equally close ones the better-known games.

Elite Dangerous
Shared: Space Sim · Simulation · Space

SpaceEngine
Shared: Space Sim · 3D · Space

Kerbal Space Program
Shared: Simulation · Space Sim · Space

War Thunder
Shared: Action · Simulation · Combat

X Rebirth
Shared: Simulation · Action · Space Sim

ARMORED CORE™ VI FIRES OF RUBICON™
Shared: Action · Third Person · 3D

X4: Foundations
Shared: Simulation · Space Sim · Space

Avorion
Shared: Space Sim · Space · 3D

Starpoint Gemini 2
Shared: Simulation · Space Sim · Action

EVE Online
Shared: Space Sim · Simulation · Space

Warhammer 40,000: Space Marine 2
Shared: Action · Third Person · Sci-fi

Dead Space (2008)
Shared: Action · Third Person · Space

Hardspace: Shipbreaker
Shared: Simulation · Space · Space Sim

Universe Sandbox
Shared: Simulation · Space Sim · Space

Goat Simulator
Shared: Simulation · Action · Third Person

Rebel Galaxy Outlaw
Shared: Space Sim · Action · Simulation

STAR WARS Jedi: Survivor™
Shared: Action · Third Person · Sci-fi

SPORE™
Shared: Simulation · Space · Action

House of the Dying Sun
Shared: Action · Simulation · Space Sim

Dyson Sphere Program
Shared: Simulation · Space · Sci-fi

STAR WARS™ Battlefront™ II
Shared: Action · Space · Sci-fi

SpaceBourne 2
Shared: Space Sim · 3D · Third Person

Trailmakers
Shared: Action · Space · Colorful

Space Engineers
Shared: Simulation · Space · Space Sim