You almost had me thrown - the cupola and sponsons screamed "British" but it just didn't look right ...
A7V/U
In case anybody wants a Civilopedia entry:
"A7V/U - Allegmeine-Kriegs-Department 7, Abteilung Verkehrswesen (General War Department 7, Traffic Section) / Umlaufende Ketten - (all-round tracks). Its design was by Vollmer based on original A7V but featured sponsons and all-round tracks (features copied from British tanks). Armament consisted of two Belgian Maxim Nordenfeld 57mm or Russian 57mm Sokol or German 77mm guns mounted in side sponsons along with four to six 7.92mm Maxim 08/15 machine guns.Its suspension was based on Holt tractor (just as A7V) and was 8.5m long.Maximum speed was 12.5km/h and it was powered by two Daimler engines (just as A7V) producing 210hp. Armor protection ranged from 20mm to 30mm and entire tank weighted 39.6 tons. A7V/U was operated by the crew of 7 men. It resembled British Mark IV (Hermaphrodite) tank but was larger." (from "achtungpanzer.com")
Best,
Oz