Hide media on external sd card, lollipop and above

I want an app that can hide/encrypt selected pictures and video on the external memory card without moving them to internal storage where space is at a premium. This is the problem with Keepsafe and other popular apps in this category. I have rooted my phone & am using the Xposed media scanner module to exclude a hidden directory on the memory card, and done the platform.xml workaround to make the external card writable. I've also wanted to try the symbolic link trick by placing the files on an ext2 formatted partition on the memory card used for link2sd and then ln -sf from the internal storage, but that doesn't work either. The media scanner exclusion works, but the files themselves are still readable on the memory card. Is there any app, even a root requiring one, that can encrypt or hide the files as they are despite the stupid restrictions put in since Kitkat?