Absolutely! It’s extremely easy once you know how it’s set up.
First, download this file (direct link, will download automatically) https://github.com/Blinue/Magpie/releases/download/v0.5.2/Magpie_v0.5.2.zip
Unzip the file to a location where it’s easy to access.
When unzipped, open Magpie.exe. It should give you the following window:
The default hotkey to enable and disable the program is Alt+F11. Don’t use it yet unless you want to fullscreen upscale whatever window you have open
The first dropdown is where you can choose the upscaling method. You’ll want to pick FSR, or some of the others to try out. The options ending with x2 and x3 are magnifications, these can be avoided.
The second dropdown is the capturing method, WinRT should be selected by default and left on that.
The third dropdown are injection methods if Google Translate is correct. Default option should be fine(2 of 3). The first option (1 out of 3) seems to be ‘no injection’, which is probably useful for games using online anti-cheat.
Then there’s a checkbox on the bottom right, that’s a frame counter. I leave it off personally.
Once that’s set up it should be good for any application you throw at it.
Now for MSFS;
Set the game to use 100% render scaling. More or less to your liking, but 100% gives best results. TAA is best left enabled as it gives the cleanest image with the given options.
Now run MSFS in windowed mode, at a resolution smaller than your native display. This will be the window it will upscale to fullscreen. Keep it around the same aspect ratio to avoid black bars around the screen.
Once you have them both running like below, click the MSFS window and press Alt+F11. Easy as that! To get back to the normal view, just press Alt+F11 again. As always with FSR, the higher base resolution, the higher quality the final image is.
Edit: I should add;
For maximum potential performance, you can combine TAAU and FSR if you’re fine with the added artifacting this can lead to.
Example; you can have a 1080p render resolution (lower render scale), upscaling to a 1440p window using the sim’s TAA, then using FSR as the final upscale to 2160p.
The final result can still be reasonably impressive, this image was scaled from 871p to 1583p to 2160p