When I select a course from my watch or edge does the other turn on automatically so I don't have to hit start on both?
When I select a course from my watch or edge does the other turn on automatically so I don't have to hit start on both?
No, it doesn't turn on.
But if you use Physio True Up on both devices, an activity completed on one device will show up on the other when you sync both devices with Garmin Connect.