The one example that I am aware of is the German preference for the Russian PTRS and PTRD anti-tank rifles over their own equivalent weapons. This was a practical preference, and was not motivated by the weapon's aesthetics or collectability in the same way that the luger was. The German anti-tank rifle (the Mauser 1918 T-Gewehr) was underpowered and incapable of penetrating most soviet armor.

It fired a 13.2x92mm cartridge which was eclipsed in both projectile size and powder charge by the soviet 14.5x114mm cartrage, which you can see here. The German military eventually switched to a newer rifle, called the Panzerbüchse 38/9 which fired a smaller 7.92mm projectile with a larger powder load (also pictured) but this too proved to be insufficient in stopping soviet armor. There are also many photographs depicting German troops using other Russian weapons, with the PPSH-41 being particularly common, but I can't comment as to whether this was out of personal preference or logistical necessity.