Games like Space Frontier
Games like Space Frontier include Rust, Terraria, Valheim, Enshrouded, and Starbound. We matched them by the tags players give Space Frontier on Steam (Crafting, Sandbox, Survival, Space, and Building): closest matches first, and among equally close ones the better-known games.

Rust
Shared: Crafting · Survival · Sandbox

Terraria
Shared: Sandbox · Survival · Crafting

Valheim
Shared: Survival · Crafting · Building

Enshrouded
Shared: Survival · Crafting · Base Building

Starbound
Shared: Sandbox · Survival · Crafting

Dune: Awakening
Shared: Survival · Exploration · Sandbox

ARK: Survival Ascended
Shared: Survival · Crafting · Sandbox

V Rising
Shared: Survival · Crafting · Base Building

ASTRONEER
Shared: Space · Survival · Sandbox

Space Engineers
Shared: Sandbox · Survival · Space

The Planet Crafter
Shared: Survival · Crafting · Base Building

Core Keeper
Shared: Survival · Sandbox · Crafting

ARK: Survival Evolved
Shared: Survival · Crafting · Building

The Forest
Shared: Survival · Crafting · Building

ICARUS
Shared: Survival · Crafting · Base Building

No Man's Sky
Shared: Space · Survival · Exploration

Once Human
Shared: Survival · Crafting · Building

Scrap Mechanic
Shared: Sandbox · Survival · Building

Abiotic Factor
Shared: Survival · Crafting · Exploration

Conan Exiles Enhanced
Shared: Survival · Crafting · Building

Satisfactory
Shared: Crafting · Base Building · Sandbox

Sons Of The Forest
Shared: Survival · Crafting · Base Building

Raft
Shared: Survival · Crafting · Building

Portal Knights
Shared: Sandbox · Crafting · Building