Doing a Google hangout with another GDCR event in a faraway time zone helps to bring home the GLOBAL nature of the event to attendees. I've used a cross-timezone meeting planner to determine times that work and have tentatively sent out invites to others for two hangouts; one just before our local lunchtime and another at our end-of-day retrospective.
If you like the idea, it's not rocket science. You need to remain flexible, make sure you agree on the way to communicate beforehand, and then make sure to pay attention to the time to make it happen. It may even help to ask someone other that the event facilitator to do that. It's easy for a facilitator to have so many things going on that they miss the planned window. Bummer.
-- Bob Allen