Any best practices for managing multiple libraries / devices?

So, I use beets for managing my music on my machine/server and it’s great. However, I’m attempting to set up a new MP3 player that has an SD card with more storage. I had intended to use beets queries to copy over music to the SD card location; however, it seems like it would be handy to be able to have a beets config.yaml for the device and manage the sd card as a second library.

I’ve been playing around with attempting to set the BEETSDIR, but have not managed to get my beets set up to recognize a config.yaml file other than the default. Part of this is that I find the BEETSDIR docs fairly shallow. Any one have more information on how to set up a second beets library config? Am I barking up the wrong tree for managing my mp3 player?

One simple solution is to move the 3 important files into a new directory-- config.yaml, library.db, and state.pickle. Then you can create a new config.yaml file and start a new db. When you are done, move the files back and your main library will be unaffected.