Why isn't possible to port TSC content to TSW4? As its from the same developers. I'd love to drive to a Pendolino from my TSC collection on TSW4.
Because they are completely different games that work in very different ways on two completely different engines. Quite frankly, it's impossible. DTG have experimented with importing track plans from TS but it didn't work very well, and as far as I'm aware that was the total extent of the experimentation. There is no way to get trains from TS into Train Sim World. It is possible to use the same models for assets and trains by exporting them as FBX files (the file format used by Unreal for 3D models) but this is not a direct conversion, although scenery assets are very easy to port over and you will likely have seen Train Sim assets in TSW multiple times - many of the stations on SEHS are from the TS version, Brighton station is from the TS version, and the old Kuju van used to be used although has been replaced by a Mercedes Sprinter-based one. Some TSW assets have also gone the other way, the LIRR M3 was ported to TS, the BR187 was, the TEAs, the 47 (I think) and the new DTG Mark 2s too, although since we have the AP Mark 2s they wasted their time with that... Trains are a lot more complicated. You need more detailed models as you can get right up close to them, and you need a proper interior, and you need to have animations for all of the doors inside and out. And even if you used the same model unchanged (which you should never do) you'd still need to write the physics simulation from scratch.
That’s like asking someone why can’t I put petrol into my diesel engine. Two entirely different games, running two entirely different game engines.
Matt has stated quite recently they briefly tried a conversion programme for track databases but it left so much to be done it was quicker to start from scratch. Going forward all TSW routes are being built with high res LIDAR DEM data as opposed to the 30m (or lower) used on most TSC routes. 3D models can only be used if the Blender or Max source files still exist. Then the process for applying shaders and effects etc. in UE is very different. tl:dr - No.
We just discussed that topic 3 days ago. Short: Two different games, two different game engines (TSC its own one I believe and TSW Unreal Engine), no possibility to port much stuff of TSC into Unreal. Long: Here is the answer of Matt (executive producer): https://forums.dovetailgames.com/threads/can-classic-routes-be-used-in-tsr4.80828/#post-830476