Games like TerraGenesis - Space Settlers
TerraGenesis - Space Settlers. These games share the most with it, and each one says why.

Idle Pocket PlanetUpdated
Also idle, space, planet
Combine settlements and ships on small planets to build new constructs, colonizing strange galaxies and filling a journal with artifacts.

To The Core
Also space, planet
Fly between planets, drill for resources until fuel runs out, and buy upgrades so each dig reaches deeper than the last.
93% steam
Angel Legion
Also space, factions
A 3D hero-collection RPG where resources build up automatically. Recruit and dress a roster of angels across three warring space factions.
85% steam70% idle
Space industrial empire
Also space, planet
Lay out flat conveyor lines for mining, smelting and research, then build warships to take other planets.
87% steam70% idle
Idle HumanUpdated
Also science, idle
Build a human body starting from one cell, adding bones, organs, nerves and muscles along the way.

Idle World - Planet MinerUpdated
Also idle, planet
Shape a barren planet by upgrading ground, plants and animals to earn energy and eventually unlock an atmosphere.

Planet Evolution: Idle ClickerUpdated
Also idle, planet
Tap a planet to gather coins, attract objects to decorate it and use prestige to push across the universe.
50% idle
Cell to Singularity: EvolutionUpdated
Also idle, science
Click through the history of life from primordial soup to technology, climbing a science tech tree.

Idle Dot Shooter!Updated
Also idle, space
A minimalist shooter where a turret fires on its own at drifting dots while you buy defence, drone, and economy upgrades and push into tougher galaxies.

Idle Airport Tycoon - PlanesDormant
Also idle, science
Build an airport, buy planes, and fund research into new transport tech while keeping passengers happy to grow profits.

ExoMiner - Idle Miner UniverseUpdated
Also idle, space
Start with one small mine and a ship, then expand to other planets, crafting materials and inventing tech while miners and rovers work in your absence.
75% idle
Idle Area 51Dormant
Also idle, science
Salvage a crashed UFO, research alien tech at a secret desert base, and run cover-up campaigns to keep the public from noticing.

Planet Smash : Idle WarsUpdated
Also idle, space
Destroy planets with missiles that fire on their own or with taps for speed, upgrading elemental weapons and collecting coins earned offline.
50% idle
Valor Legends: Idle RPGUpdated
Also idle, factions
Summon heroes from five factions, arrange them in rows, and let them fight automatically, sending them on bounties for bonuses while you are offline.
75% idle
Idle evolution: Life on EarthUpdated
Also idle, science
Guide life from the ancient seas to human culture while learning about prehistoric creatures along the way.

Mega Tower - Casual TD GameUpdated
Also idle, space
Merge and modify towers in a sci-fi tower defense that fights on its own but lets you aim manually.
50% idle
Astro BuilderUpdated
Also idle, space
Build a space station in orbit, turning materials from a space elevator into platforms and new equipment.

Human Evolution - Idle ClickerDormant
Also idle, space
Tap to drive life from single cells through fish, apes and humans to cyborgs and beyond, then seed evolution on other planets.
25% idle
Rocket Star: Idle Tycoon GameUpdated
Also idle, space
Run a spaceship factory, research new tech and launch rockets toward the Moon, Mars and outer planets while your staff keeps earning in your absence.
75% idle
Idle Space Farmer ManagerDormant
Also idle, space
Run an anime-styled space farm, recruiting agents from gacha pulls to fight monsters and upgrading ships across planets with prestige.
75% idle
Eternal Evolution: Idle RPGUpdated
Also idle, factions
Collect over 100 sci-fi heroes across three factions and lead squads into battle, with resources flowing in while you are away.
75% idle
Idle Ant Colony - Sim GameUpdated
Also idle, science
Grow an anthill by hatching workers, laying trails to haul food and researching new tech to found colonies on other continents.
75% idle
Idle War: Legendary HeroesUpdated
Also idle, factions
Summon from over 100 heroes across six factions for Norse myth battles that run fully automatically, even offline.
90% idle
Mini Legion: OutlandUpdated
Also idle, factions
A medieval fantasy idle MMORPG with rival factions, guild wars, dungeons and weapons that grow with you.