You can get an adapter like the Mayfair Magic NS and hook up an Xbox adaptive controller. Yeah it's an extra $20 it maybe shouldn't be but on the plus side you can then share the controller among a PC/Xbox/Switch.
“Non-standard controllers” being devices that basically amount to cheating, either giving you mouse+kb input with controller aim assist, or giving you access to things like recoil compensation scripts.
The issue with using mouse+kd on consoles is if it's done using a 3rd party device then the console can't detect it and aim assist can still be used.
If the game natively supports mouse+kd then that is fine but if you are using mouse+kd with aim assist turned on then you are basicaly using an aimbot to cheat.