I've found myself with similar trouble. I want to export plans from iFly to Dynon Skyview. (They can talk via wifi, however the Dynon setup doesn't have a wifi adapter, so for now I can only use files.)
For now, I've discovered that SkyVector can export a plan in both .fpl and .gpx formats. I later learned, via the FAQ (but not the manual), that iFly can import .gpx plans in a somewhat roundabout way.
So for now, my setup is: 1) make a flight plan in SkyVector 2) export that plan as a .gpx file 3) use the roundabout way to get that .gpx loaded into iFly as described in the FAQ 4) load the same .gpx file into Dynon Skyview. Altho roundabout, it succeeds at getting the same plan on both my EFBs.
I would be able to avoid the third party tool if I had the Skyview wifi adapter, or else if iFly could export .gpx files on its own. Hopefully the latter is in the "new features" pipeline.