Best overlap: 8:00 AM to 4:00 PM in Shenzhen is 10:00 AM to 6:00 PM in Brisbane.
Plan around 8:00 AM to 4:00 PM in Shenzhen, which is 10:00 AM to 6:00 PM in Brisbane, to catch everyone during office hours. Brisbane is 2 hours ahead of Shenzhen, but with 8 hours of common ground you can hold morning or afternoon meetings without anyone working odd hours.
The US to Australia gap runs 14 to 19 hours depending on the month, and someone is always in tomorrow. Exact overlap windows for every US coast, the double-DST trap, and a rotation rule that keeps it fair. -