A:AnswerSound leakage is minimal in my opinion. Long as they are flush to your ears you will enjoy these. I workout in them and mow the lawn and sound is great.
A:AnswerThere us no usb dongle or ‘transmitter’, just the headphones. Pairing/using the headphones must be done with a device already Bluetooth capable.
Does the Joey have Bluetooth built in? If yes, you’re in business. If not, there are aftermarket Bluetooth transmitters you can add via USB to some devices that lack Bluetooth, but they can be flaky.
A:AnswerThere might be a second delay. You turn it on it says how much percent you have and then it connects. If that is too much of a delay then find something else.
A:AnswerI don't know about Xbox but I can say for sure that you can't use Bluetooth headphones with a Switch without some sort of adapter/Bluetooth transmitter.