@jernserval said in More 8BitDo Pro 2 Controller Weirdness:

It appears there's some kind of naming conflict or problem when the 8BitDo tries to "spoof" as an XBox One controller?

No, I don't think so - conflicting with what ?

Xpadneo refers to configuration in it's docs, but there was no configuration after RetroPie-Setup install?

Configuration is optional, RetroPie doesn't add any, but you can add it if you'd like.

hid_xpadneo: loading out-of-tree module taints kernel. - Does this mean I need to install the headers referenced in the xpadneo documentation? Was it not autoinstalled by RetroPie-Setup?

No, that means what it says - it's an out-of-tree module, external to the Linux kernel. Kernel headers are already installed, otherwise the module wouldn't have compiled.

Now in retroarch its saying "8BitDo Controller not configured" why would it say explicitly "not configured"?

Because it's not configured ? This means there was not configuration profile found for the controller.

What is the way forward to get the most reliable experience with X-Input across retroarch and other emulators?

You haven't mentioned the issues you have with other emulators, but for RetroArch it's enough to configure the controller in EmulationStation in order to generate the configuration for it.

xbox wireless controller - xbox button not working