Having updated both the Steam Client and Steam Link to the latest betas I was able to get native Switch Pro Controller support to function properly. However quite often (once every 1 - 5 minutes) my inputs will begin to be read at a significant delay followed by outright disconnecting my controller, which then reconnects after a few seconds (apparent by the screen freezing for a split second and the "Switch Pro Controller" popup appearing in the bottom right of the screen). Input will then continue as normal but depending on the game, the game may refuse to continue to read inputs so I need to exit the game entirely.