I think its worth taking a look at the demo and try it out. And you can fly the Space Shuttle and the Jumbo transporting it. This forum may have some good archives to help you get started, especially this thread. But it is much easier to assign all joystick buttons, the included openstreetmap of the world makes it really easy to find you way doing VFR flights and there are plenty of freeware planes available (ok, there are much more FSX planes, but I am sure that will increase in future). The world’s most advanced flight simulator just got an upgrade. Multiplayer servers is not a service X-Plane provides at this time.

Decentralized hostless and efficient peer-to-peer networking. Meet new pilots and fly together in Microsoft Flight Simulator 2020, Prepar3D, X-Plane, FSX:Steam and FSX. JoinFS for Microsoft Flight Simulator 2020 JoinFS for X-Plane 11 or later JoinFS for FSX or Prepar3D.

I did not find the way to have several views the same time on a screen or changing a plane is not possible during flight (ok, might be reasonable for a realistic simulator.) And ATC is really manual work instead of the couch potato way in FSX. JoinFS Multiplayer Across Flight Simulators Choose Version.

But a few things are for me very different to FSX or I at least have not figured it out how it works. Right now I am making me familiar with X-Plane since the graphics are really eye-candy, especially clouds (although they can cut framerates to a level where really hurts). Yes, I read about the plans of MS regarding FSXI or however it will be called.

X plane 10 multiplayer