Click on Track headers whilst holding down Ctrl to select individuals, or holding Shift to select a contiguous series..... this groups all controls, including Automation.
Should work fine if you Record the Autom at same time using the grouped Faders to control the volume;
or are you trying to apply Autom written for one track to another track?
or trying to Edit Autom for one track expecting others to follow?
Your OP said "any way to set automation across multiple tracks at same time" - maybe you should expalin what you are doing / trying to do more precisely .....