This adapter finally works officially for Nintendo Switch owners looking to use their previously useless Stadia controllers on the Switch console, and it's terrific! You first have to unlock your Stadia controller to make it a Bluetooth controller on the Stadia official webpage. Once that's done, go to the 8bitdo official website, click on the firmware update link, choose to update for Windows or Mac, then download the firmware update tool that you will unzip and open on your computer. In the firmware update tool you will need to connect the adapter to your computer, then run the update. The latest firmware version (1.05 I believe) allows the Stadia controller to work on your Nintendo Switch. You'll need to connect the adapter to the Switch dock, turn on the console, go to System Settings-->Controllers and Sensors-->Pro Controller Wired Communication and set it to "On". Now go to Controllers from the home page and select Change Grip/Order. You may need to press or hold down the sync button on the adapter before it works the first time, but if you do it correctly, the Stadia controller will be recognized and connect just like the Pro controller. You do lose some of the features of the Pro controller, but it works in-game as a great substitute or additional controller.