Games like War Platform
Games like War Platform include War Thunder, Men of War: Assault Squad 2, Mount & Blade II: Bannerlord, Ultimate Epic Battle Simulator 2, and Call to Arms. We matched them by the tags players give War Platform on Steam (Simulation, War, Vehicular Combat, Naval Combat, and RTS): closest matches first, and among equally close ones the better-known games.

War Thunder
Shared: Vehicular Combat · Simulation · War

Men of War: Assault Squad 2
Shared: War · Simulation · Strategy

Mount & Blade II: Bannerlord
Shared: War · Strategy · Simulation

Ultimate Epic Battle Simulator 2
Shared: Simulation · Strategy · God Game

Call to Arms
Shared: RTS · War · Strategy

Totally Accurate Battle Simulator
Shared: Simulation · War · Strategy

UBOAT
Shared: Simulation · Naval Combat · War

Arma Reforger
Shared: Simulation · Shooter · War

Sea Power : Naval Combat in the Missile Age
Shared: Simulation · Naval Combat · Strategy

From the Depths
Shared: Vehicular Combat · Naval Combat · RTS

Arma 3
Shared: Simulation · Action · Shooter

Freeman: Guerrilla Warfare
Shared: Strategy · Shooter · Action

Holdfast: Nations At War
Shared: War · Shooter · Simulation

Carrier Command 2
Shared: Simulation · War · Strategy

Hell Let Loose: Vietnam
Shared: Simulation · Strategy · War

Total War: WARHAMMER II
Shared: War · Strategy · RTS

WARNO
Shared: RTS · War · Strategy

Wargame: Red Dragon
Shared: RTS · Strategy · War

War on the Sea
Shared: Simulation · Strategy · Naval Combat

Total War: WARHAMMER
Shared: Simulation · Strategy · RTS

Ravenfield
Shared: War · Shooter · Action

Aimlabs
Shared: Simulation · Shooter · Action

Kingdom Heroes 8
Shared: War · RTS · Strategy

Ultimate Admiral: Age of Sail
Shared: Simulation · Naval Combat · Strategy