That's almost correct. Put ActiveChans and AI.ADCTimingMode in the same property node (drag the bottom to select two properties) and wire it into your task, and I think it should work. ActiveChans has to be first because it applies to all of the properties below it in the same node.
Thank you very much Brad. Thanks to your step-by-step instruction, now the VI works with 2 analog input synchronised.
I simulate two devices (cDAQ9174+9206) and run Acq Voltage-Clk Select.vi. It does work.