You need to enable Pro Controller/Wired Controller in the settings on the Switch.
1. Plug adapter into console
2. Press POWER to turn on your controller.
3. Press both PAIR buttons on the receiver and controller to sync them.
4. Both LEDs on the receiver and controller will become solid when they are successfully paired.
5. Hold Left on DPAD and Select for 3 seconds, Receiver blinks and then becomes solid
It's one controller per USB adapter.
The adapter only supports one joy-con at a time, in the sideways mode.
Our USB Adapter is compatible with Xbox One S/X Bluetooth controller now. Please upgrade its latest firmware to V1.13.
1 * 8Bitdo USB Wireless Receiver