Question about Peak Design Everyday Sling v2

idk how big is the drone but if you plan to get the camera in and out comfortably i would not advise it. If you're okay packing it tight without extras (wallet, keys, passport...) then that could work.
6L is not that big, also doesn't have a ton of support for your shoulder if you're planning to carry it for a while.

I have an X-H2 and store the camera with 85mm in the bag, plus two or three other lenses. So that should work well for you with the bag.