Guys have looked for that for years with the racing sims.

Some of the sims let you push a button to look out the car's left side and another button to look out the right side. The guys wanted to run 3 monitors with the side views always up on the side monitors. But unless the software knows to always send 3 views consecutively, and ignore the buttons' positions, it wasn't going to work.

To get different views, the software has to produce them. Most software only produces the one view you are using at that moment in order to churn the fewest cycles. Some of the "view" you see is created by the application's mainline code that passes that off to the video card. So if you want to see two views at once, the application would need modification to work the code that creates one of the views and also work the code that creates the other view. I'd guess that functionality isn't designed into most flying sims or it'd be advertised like crazy.