Games like Stonedeep
Games like Stonedeep include Oxygen Not Included, RimWorld, Frostpunk, Manor Lords, and Factorio. We matched them by the tags players give Stonedeep on Steam (Base Building, Colony Sim, 2.5D, Survival, and Resource Management): closest matches first, and among equally close ones the better-known games.

Oxygen Not Included
Shared: Base Building · Colony Sim · Survival

RimWorld
Shared: Base Building · Colony Sim · Survival

Frostpunk
Shared: Survival · Resource Management · Colony Sim

Manor Lords
Shared: Base Building · Simulation · Building

Factorio
Shared: Base Building · Resource Management · Survival

Prison Architect
Shared: Base Building · Colony Sim · Building

Against the Storm
Shared: Base Building · Simulation · Building

Dwarf Fortress
Shared: Colony Sim · Base Building · Simulation

Kingdoms and Castles
Shared: Colony Sim · Resource Management · Base Building

Space Haven
Shared: Base Building · Colony Sim · Survival

Banished
Shared: Colony Sim · Survival · Simulation

Empires of the Undergrowth
Shared: Base Building · Colony Sim · Simulation

Dyson Sphere Program
Shared: Base Building · Resource Management · Building

Workers & Resources: Soviet Republic
Shared: Base Building · Simulation · Building

Satisfactory
Shared: Base Building · Building · Resource Management

Norland
Shared: Base Building · Colony Sim · Simulation

Settlement Survival
Shared: Colony Sim · Survival · Building

IXION
Shared: Survival · Colony Sim · Base Building

Ratopia
Shared: Colony Sim · Base Building · Building

They Are Billions
Shared: Base Building · Colony Sim · Survival

Planetbase
Shared: Colony Sim · Base Building · Survival

Endzone - A World Apart
Shared: Survival · Base Building · Colony Sim

Cities: Skylines
Shared: Building · Simulation · Management

Timberborn
Shared: Colony Sim · Base Building · Building