>>1450064>German designs/patents were practically free game after WWII resulting in lots of Soviet bloc countries producing cheap copies of German manufactured goods, and I wouldn't be surprised if locomotives were also copied and built.
Here in Poland no brand-new locomotives were designed using German patents, in fact, the only "German" locomotives made after the war were classes Ty42 and Ty43, or rather assembled from parts that were left by Germans. Other than that, these were identical to captured "Kriegslokomotiven" designated class Ty2 and Ty3 respectively after the war, so not exactly "copied".
It was more common to build locomotives based on the pre-WW2 period designs: Ty45 was based off the Ty23 (albeit the "bathub-style" tender is a very visible German influence), Pt47 is a evolution of Pt31 (as mentioned above) and the narrow-gauge Px48 is essentially a modification of class Px29, whose blueprints survived the war. An example of combining both Polish and German design principles is the class TKt48 tank locomotive, mostly inspired by the pre-WW2 class OKl27 but also does have the 1-4-1 wheel arrangement taken directly from DRG class 86 (later TKt3 on PKP). A very successful locomotive that lasted in revenue service until the end of mainline steam operations.>Could also be a result of pre-WWI Imperial Germany's influence.
The famous Prussian P8 (later DRG class 38, PKP Ok1) heavily influenced the design of PKP class Ok22, to the point of having nearly identical tender and running gear. The first few examples were actually built by Hanomag before serial production began at FabLok. Polish pre-WW2 locomotives were also inspired by Austrian and Russian designs (class Os24 for example is a Polish-designed one, but similarities to Austrian locomotives are uncanny, smokebox in particular). Also I think that Wurttemberger class C Pacific might have inspired PKP to experiment with 2-3-1 wheel arrangement (class Pm36), but this never took off.