Don't get me wrong, I cannot speak, read or understand German for LOVE, but if anyone can make sense of the linked post, I would love to see the route/loco in TSW5, took one look at it and fell in love, we don't have any 1-car (by default) units, we need this Link: https://www.instagram.com/p/DCUj6PntOBW/?igsh=bm5pOThwZ21oa2tx
What the instagram post says is basically the same information you can find on Wikipedia for the BR 670 with a few special notes to the one used on the Weimar-Kranichfeld line. In short, There were only a few of them finished (6 with the demo-car), used for some smaller branch lines in East Germany and the Mosel valley. Due to its high failure but also the omission of electric air condition and toilets, they were taken from service quite quickly thereafter. DB had them for a few years but then handled them back to the manufacturer who sold them to smaller private operators. If we had the Koblenz-Trier railway in Train Sim World, it could be used on the branchline Bullay-Traben-Trarbach. It also could be used for the route Dessau to Wörlitz, creating a route hop opportunity to Rapid Transit, but DTG would need a license with the Dessauer Verkehrs- und Eisenbahngesellschaft mbH to use "Lordess Louise" and "Lord Franz". You can use auto-translated subtitles to english There even is a cab (deck) ride available lol