The camera does not have a built-in microphone. The console's own microphone is used for voice communication on the Nintendo Switch 2, while the camera is intended for video chats via the GameChat function. External USB-C microphones can also be used, as the camera itself does not have an integrated microphone.
Unfortunately, there is also no tracking with this camera. You do have the option of making the predefined circle larger, but then the head is simply smaller in comparison and the facial expressions are therefore less visible.