We working on a resolution for this with Edge devices and compatible wearables.
I own an Edge 830 and just got also the new Fenix 6.
It's very annoying that Garmin connect does not know to sync the information between the devices.
+1 for this issue, this is the only reason I don’t buy a new fenix 6 yet. Please fix it Garmin! Thanks!
I use a Fenix 5X and an Edge 520. I would definitely like to have them able to combine stats and hopefully we'll get that feature at some point but until then what I do is use both during a ride. They are both paired to the same sensors (HR, power meter, etc) and for the most part once I start the activity on the Fenix I ignore it until I'm done and end the activity. I then save it on the Fenix and make sure it syncs. As long as it does I then discard the activity on the Edge, if for some reason it didn't sync I'd save the Edge activity instead. This is hardly ideal but I prefer the Edge display while cycling but want combined stats so this is how I do it. Another option some people use is to sync the devices to separate Connect accounts and then just use one as their primary.
You’ll see more/better integration of FirstBeat going into Q1 2018, mostly on the backend for things like cross-device sync between multiple devices (Edge/Vivo/Fenix/Forerunner), as well as site/app surfacing of that information.
You’re starting to slowly see things. Garmin is keenly aware of the gap here and looking to remedy. As they themselves noted ‘it’s impacting our best customers’. It won’t be a switch overnight, but you’ll just start seeing the individual gaps be filled one at a time.