Games like Mardori
Games like Mardori include Elite Dangerous, STAR WARS™: Squadrons, X Rebirth, No Man's Sky, and Kerbal Space Program. We matched them by the tags players give Mardori on Steam (Simulation, Crafting, Singleplayer, Sci-fi, and Space): closest matches first, and among equally close ones the better-known games.

Elite Dangerous
Shared: Space · Simulation · Space Sim

STAR WARS™: Squadrons
Shared: Space · Singleplayer · Simulation

X Rebirth
Shared: Simulation · Sci-fi · Space

No Man's Sky
Shared: Space · Sci-fi · Singleplayer

Kerbal Space Program
Shared: Simulation · Space · Space Sim

X4: Foundations
Shared: Simulation · Space · Space Sim

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

Endless Sky
Shared: Space · Simulation · Sci-fi

SPORE™ Galactic Adventures
Shared: Simulation · Space · Singleplayer

FTL: Faster Than Light
Shared: Space · Sci-fi · Singleplayer

Microsoft Flight Simulator X: Steam Edition
Shared: Simulation · Singleplayer · Realistic

Starfield
Shared: Singleplayer · Space · Sci-fi

Microsoft Flight Simulator (2020) 40th Anniversary Edition
Shared: Simulation · Singleplayer · Realistic

Trailmakers
Shared: Space · Singleplayer · Action

Rebel Galaxy
Shared: Space · Sci-fi · Singleplayer

Spaceflight Simulator
Shared: Simulation · Space · Space Sim

Starpoint Gemini 2
Shared: Simulation · Space · Sci-fi

Deliver Us The Moon
Shared: Sci-fi · Space · Singleplayer

SpaceEngine
Shared: Sci-fi · Space · Space Sim

Universe Sandbox
Shared: Simulation · Space · Space Sim

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

Drug Dealer Simulator
Shared: Simulation · Singleplayer · Crafting

V: Rings of Saturn
Shared: Sci-fi · Space · Singleplayer

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