I have no idea if this works but my guess is you need an app that converts 2D video as a split screen stereoscopic 3D video. Like this one claims (never tried it):
https://forums.androidcentral.com/e...=com.funghisoft.sbsvideoplayer&token=RYD7khIq
Also, YouTube now supports 3D stereoscopic video if you can get your drone to stream video to YouTube then watch YouTube on Gear VR through your note 4.
One drawback with this approach is that currently there is no YouTube app built for Gear VR. You can still do it but you have to mount the phone into Gear VR WITHOUT plugging into the micro usb port.
When you do this, the head tracking uses the phone's accelerometer which is nowhere near as precise and as fast as the Gear VR accelerometer. So your video might be laggy/jumpy a lot, making you sick.
Good luck! Post back if you get this to work.