When you take the switch out the dock the external drive just unmounts and the game list refreshes. Also took it out while running game to see what happens. Doing it in Bayonetta 2’s menu just caused the music to stop, starts again when plugged back in. Taking it out during loading screen caused...
I had to put all the xci’s on to the root to get it to work.
Edit: Usb 3 2.5” drive is now working just plugged in without external power. Takes a bit longer to load vs using external power but seems to be working fine.