I just a youtube video showing a br 182(german) looking loco that was desiel powered it had no pantograph on top of the loco,it was on a county type of track with no catinare overhead,so why not take the 182 and modafie it into a desiel version,it would need some changes to the cab to fit the desiel control system into it,but at least you won't have to build it from the ground up.
I'm not sure where you found such a video, but there is as far as I know no diesel version of the Eurosprinter, or in DB terms the BR 182. From the newer version of the Eurosprinter, the Vectron, is a diesel version though, I'm not sure if you meant this one. The vectron is available in both electro and diesel configurations. Here's a picture of the diesel variant of it: https://en.wikipedia.org/wiki/EuroSprinter Notice the first sentence: "The EuroSprinter family of electric locomotives is a modular concept of locomotives..." Still, the Vectron could be a very cool addition to the game
I wonder if this could have a german loco modified for use in another country,the youtube title was a laungage i didn't know,i couldn't make out the locos id number but it did have a large Q on the side and it was based on a 182 model.plus it was painted the same color as the other german locos in the game.
The Austrian and Slovenian trains also have a sort of the same shade of red. I've found two images that could've been what you've seen: First, this is a Taurus from the Slovenian Railways. You can see how the pantographs are down and there are exhausts, but it is no diesel! Those are radiators and the locomotive is shutted down in this state. Second image. This is an older version of the Eurospinter, which was available in diesel or electro configurations, but it doesn't look like a 182: This one is owned by the Austrian Railways, the ÖBB. The Ö kinda looks like a Q somehow, so this could've been the train you saw.
There is dual mode Vectron too https://new.siemens.com/global/en/p...ling-stock/locomotives/vectron/dual-mode.html
The 2nd one might have been the one i saw,but i'll have to try and find the video again,in video it had 2 locos and was pulling some sort of service train,maybe for track repair,there was mostly all blue and black paint color on the train cars it pulled.