Games like PlayFortress
Games like PlayFortress include Banished, Foundation, Mount & Blade II: Bannerlord, Cities: Skylines, and Totally Accurate Battle Simulator. We matched them by the tags players give PlayFortress on Steam (Strategy, Simulation, Early Access, Indie, and Medieval): closest matches first, and among equally close ones the better-known games.

Banished
Shared: Strategy · Simulation · City Builder

Foundation
Shared: Simulation · Strategy · Medieval

Mount & Blade II: Bannerlord
Shared: Strategy · Medieval · Sandbox

Cities: Skylines
Shared: Simulation · Strategy · City Builder

Totally Accurate Battle Simulator
Shared: Simulation · Strategy · Sandbox

Ultimate Epic Battle Simulator
Shared: Simulation · Strategy · Sandbox

Cities: Skylines II
Shared: Simulation · City Builder · Strategy

Crusader Kings III
Shared: Strategy · Simulation · Medieval

Manor Lords
Shared: Strategy · Simulation · City Builder

Life is Feudal: Forest Village
Shared: Strategy · Simulation · City Builder

Ostriv
Shared: Strategy · Simulation · City Builder

Stonehearth
Shared: Strategy · Simulation · City Builder

Kingdoms and Castles
Shared: Simulation · Strategy · City Builder

Songs of Syx
Shared: Strategy · City Builder · Sandbox

Crusader Kings II
Shared: Strategy · Medieval · Simulation

Prison Architect
Shared: Simulation · Strategy · Sandbox

Dawn of Man
Shared: Strategy · Simulation · City Builder

Tavern Master
Shared: Simulation · Strategy · Medieval

Transport Fever 2
Shared: Strategy · Simulation · City Builder

Anno 1800
Shared: Strategy · Simulation · City Builder

TheoTown
Shared: Simulation · Strategy · City Builder

Settlement Survival
Shared: Simulation · City Builder · Strategy

Dwarf Fortress
Shared: Simulation · Strategy · Sandbox

Plague Inc: Evolved
Shared: Strategy · Simulation · Indie