This would be a perfect project for students as a science fair entry, but the answer is pretty simple and depends on the time of day and the lunar phase. If you see the Moon in the daytime, it is certain that someone will be looking at the same Moon, either before sunrise, or after sunset in the 'night time' sky. You don't have to make the trip to China to see this duality played out. For observers on opposite sides of the Earth, the only lunar phase that can be seen by both parties is the Full Moon. It would be on the horizon.