There is still no option in Teams for Mac to make a test call. Despite all the assurances that it's in the device settings, it isn't. You can get a video preview of your camera output, but there is no way of checking that the mic works, not even visual feedback like the bar graph in the audio settings in Skype (which *does* also have a test call option for Mac).
In order to test that everything's working properly, I've had to download Teams on my phone, create a new MS account, and then initiate a call between my Mac and my phone. It's just plain ridiculous. Where is the benefit to either MS or the customer not to let them have a test call button on the Mac version?