Italian state railways FS Trenitalia operates in Germany using several different names. Trenitalia bought the German parts of Arriva at the time when DB took over Arriva from it previous British owners. That part is now called Länderbahn. But the old names Vogtlandbahn and Arriva Länderbahn express alex (now Allgäu Länderbahn express alex) are also often seen.

After German reunification the city of Zwickau in the east wanted a tram-train system for local traffic so that the trains could run along tram lines in the city center but use existing normal gauge, unelectrified train lines in rural areas. These RegioSprinter trains were built for the purpose. In the city center of Zwickau the tram lines have three rails so that these normal gauge RegioSprinters can run on them as well as the normal metre gauge trams. They have just one axle in the front and at the back and in the middle there is a motorised unit with a diesel engine. They are fitted with all necessary tram equipment so that they can run on normal streets under the laws governing tram traffic. These trains were built by Siemens/Dûwag, but they were never a commercial success. In 2019 most have already been sold to Czech Republic, where they are used as regular railbuses.
Picture from Zwickau 1.8.2019 by Hannu Jälkö.

Detail picture of the front of a RegioSprinter. Note that there is just one axle at the front of the train.
Picture from Zwickau 1.8.2019 by Hannu Jälkö.