With the recent news that Nintendo is making Bluetooth Audio available at last on System 13.0.0 (mid Sep 2021) this may appear to make external Bluetooth Transmitters a redundant product. However the Switch will only be able to use two controllers when used with Bluetooth Audio and may experience lag as it will not be an AptX implementation.
Devices such as our UGreen Nintendo Switch Bluetooth Transmitter avoids these limitations, if Lag Free Audio and Four Controllers are key features for your gaming you'll want one of these.

