The Expert will be specific knowledgeable people at the Department of Transport, Arrive Alive Communications, the Road Traffic Management Corporation or others who might have the expertise to answer the question.
Moving off from the Stop signs
Neither vehicle has priority over the other in terms of who may move off first. It is not a 3-way or 4-way Stop. The normal rules for a Stop sign apply: Move off only when it is safe to do so.
Moving off and turning right
The rules for turning right at an intersection apply. The vehicle that is intending to turn right must give way to any approaching traffic that is close enough to represent a potential hazard. In other words, both vehicles can move off independently from their respective Stop signs, but the one that is turning must give way to the the approaching (non-turning) vehicle unless it is so far away that it is nevertheless safe to execute the turn. If there is a crash, the turning vehicle's driver could be liable for unsafely turning across the path of oncoming traffic.