a big [#welcome] to the MR forum - you found the right place. There are lots of friendly and helpful people here who sure can answer any question you may have.
On your issue of integrating a stretch of US prototype trackage (and trains) to a mainly European (Alpine?) based layout - yes, sure this can be done, but we would need a diagram of your layout to see where it would fit best.
Without knowing your layout it is quite difficult to give you any meaningful advice.
My late cousin used to run his European and American models side by side on the same layout – the layout itself was European in scenery and buildings. And there are cities in American, Milwaukee and Cincinnati come to mind, which feature buildings with a Germanic appearance due to the many German settlers.
I have seen German layouts which set aside an area that looks like it is filming “Wild West” films using American equipment.
The HO set is build in a room of 7.00x4.00 m. and the tables are 1.10 x 1.10 m.
G H I J K L
F
E D C B A
G H and I are a typical “german” mountain landscape, 3.30 x 1.10
Under J K and L is a shadowstation and under L a climbing ring to the top level, which is still unused.
A and B are also a typical european hill and city landscape, with german timbered limestone houses and the Calw station. 1.50 x 2.50 m.
But on both landscapes the houses could be changed or adapted. I’m still in the phase of building the landscapes.
So the tables C D and E (3.00x1.10m), F (1.10x1.10m) and J K and L (3.30x1.10m) are “bare” … without drawings this was the easiest way to “draw” the layout. The letters form more or less an H.
We visited the USA serveral times and are very fond of the whole west side of your beautiful country, we also visited Alaska and travelled through BC and Yukon.
as being a dutchman myself, some engines bought by the Dutch National RR-system (NS) just after WW2 came from the USA. Also the Noabs used in many European countries were designed in the USA.
My profile pic is from one of those American based Dutch engines.
Gidday Dini, One thing that you may have to consider running American trains on a European layout is the distance of your line side buildings, ie station platforms, warehouse loading docks etc, from your track centres as I believe that the North American “Loading Gauge” is slightly more generous than its European equivalent
One of the other things to consider is that European and North American model track and wheel standards are similar but not identical. European prototype 2-rail H0 track and wheels are built to NEM standards, whiel North American prototype models use NMRA standards. Some manufacturers (notably Trix) offer their North American models with the option of NEM or NMRA (“RP25”) wheels.
You’ll be happier with your results if you pick one set of standards or the other for your North American line. The Trix, Roco, and Piko track systems use the NEM standards, while the Atlas, Bachmann, and Walthers/Shinohara track use NMRA standards. Peco offers both - its Code 100 and Code 75 lines use Euro standards, but its Code 83 line is North American.
I’m using Märklin HO, we have the Märklin Santa Fé and the Southern Pacific, both with MFX , on Märklin C tracks, so the “big” problem is to integrate the USA trains into our European landscape and other German, Swiss & Swedish trains.
the landscape of the regions which were served by the AT&SF and the SP look very much different than Germany, Switzerland and Scandinavia. Those lines were in the “dry” part of the US.
If I understand you correctly, you won´t be running your US trains next to your European trains, but will have a separate part of your layout dedicated to them. Why then bother to make a transition from Europe to the US. Just integrated a scenic divider (i.e. tall mountain, backdrop) and have the US part modeled in that typical landscape of the Southwest?