A timing question.

Wedge Antilles is equipped with Stay On Target, BB-8 and Integrated Astromech. He reveals a green forward 2.

Can he trigger BB-8 to execute a free barrel roll, then trigger Stay On Target to switch his forward 2 to any 2 maneuver? Or would he have to trigger SoT prior to actually executing the roll and thus invalidate BB-8's activation condition?

It looks like they use the same trigger: Stay on Target is "When you reveal a maneuver..." and BB-8 is "When you reveal a green maneuver..." So you can execute them in either order.

Agreed