Hello @Tr0uBl3dShAd0w13,
Best option for promods is use separate profiles. It's hard to keep the same mod files for both single player and truckersmp as not all mods of promods is supported on truckersmp server. Even if you use only europe, great steppe and middle east even then it won't work because Truckersmp does not use the definition which comes with promods, it uses it's own. But when you load singleplayer, the definition on your mods folder will be used thus causing the content game change.
Therefore I recommend you to use different profiles for ProMods Singleplayer and ProMods Truckersmp. This is what I personally do, to avoid long waiting period on content change screen and teleporting.
You can of course copy your current profile and create two separate profiles. I use separate file for normal truckersmp, tmp promods and promods singleplayer. Here's a Link to know how to create copy of your current profile. This is the best option I can suggest.
Hope I was able to answer your question to your desired outcome. If you have more questions, do tag me here or feel free to message me on forum.
Best regards,
Aashraye