If you want to utilize all features of an 8BitDo controller at once, you also need Steam. XInput mode means no gyro, no back buttons bindable in software, Switch mode gives you gyro but makes your triggers digital, and you still can't bind the back buttons in software. You're limited to duplicating an existing input via the 8BitDo app and binding it globally at the firmware level. If you use the 8BitDo Pro 2 with Steam in DInput mode, you get analog triggers, gyro, and the back buttons are bindable in software per-game. This was not the case on release, 8BitDo and Valve worked together and gave this improved support via an update.
The software around controllers is universally bad, and Valve is the first to really try to fix it. We need a successor to XInput that is less limited.
THANK YOU
It's been driving me crazy seeing all the hate Valve is getting over compatibility concerns when Valve is the only one making controller support on Windows outside of an Xbox controller work. For years I just assumed I couldn't use many of my controllers on Windows, until Steam added the ability to act as the in between and properly handle it. Microsoft has no interest in making anything other than their Xbox controllers work, and everyone suggesting some sort of "I can just buy X as an alternative" has some major caveat that gets conveniently ignored.