A:AnswerIt is powered by a small transformer with 120vac configuration. Read the tech specs and see if the transformer is compatible with 220vac. If it is, you would just need an adapter to change the plug configuration, or buy one made for where you live.
A:AnswerOn the larger Google Home unit, you can adjust the volume manually with your finger swipe on the top or you can tell Google orally to increase or lower the volume. On the Mini you just tell Google to increase or decrease the volume.
A:AnswerI do not believe this option is available, as the mini speaker is simple a receiver and does not send out a signal for the ear buds to pick up.