Set launch options, use proton tricks. Any proton version >= 7.0 should work.

How to make it work:

1- Select any proton version >= 7.0

2- Launch fsx. It will crash.

3- use protontricks to install 'dxvk' and 'corefonts'

4- create native only override for d3d10.dll (" *d3d10 ") and d3d10_1.dll (" *d3d10_1 ") with winecfg or launch option

5-Launch again. The game should work just fine, including free-flight menu and properly flying.

Additional notes: launch option WINE_DISABLE_VULKAN_OPWR=1 should only be used if your WM is wayland-based. You can use a reduced DXVK hud with the launch option DXVK_HUD=1.