Games like Project Wunderwaffe
Games like Project Wunderwaffe include Foxhole, Oxygen Not Included, Hearts of Iron IV, Bomber Crew, and RimWorld. We matched them by the tags players give Project Wunderwaffe on Steam (Strategy, Base Building, World War II, Building, and Wargame): closest matches first, and among equally close ones the better-known games.

Foxhole
Shared: Base Building · Wargame · World War II

Oxygen Not Included
Shared: Base Building · Building · Management

Hearts of Iron IV
Shared: Strategy · World War II · War

Bomber Crew
Shared: World War II · Strategy · Management

RimWorld
Shared: Base Building · Strategy · Management

Company of Heroes 2
Shared: Strategy · World War II · War

Manor Lords
Shared: Strategy · Base Building · Building

Factorio
Shared: Base Building · Strategy · Management

Against the Storm
Shared: Strategy · Base Building · Building

This War of Mine
Shared: Strategy · Base Building · War

Men of War: Assault Squad 2
Shared: Strategy · World War II · War

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

Prison Architect
Shared: Base Building · Building · Strategy

Steel Division 2
Shared: Strategy · World War II · Military

Sprocket
Shared: Building · World War II · Wargame

Frostpunk
Shared: Strategy · Base Building · Building

Company of Heroes
Shared: Strategy · World War II · War

Empires of the Undergrowth
Shared: Strategy · Base Building · Building

Dwarf Fortress
Shared: Base Building · Strategy · Building

Ground of Aces – The World War II Airbase Builder
Shared: Strategy · Base Building · World War II

Ratopia
Shared: Base Building · Building · Strategy

Ostriv
Shared: Strategy · Base Building · Building

Stronghold Crusader HD (2012)
Shared: Base Building · Strategy · Military

They Are Billions
Shared: Base Building · Strategy · Building