Just circling back here in case anyone else comes looking for a solution.
Sync Links with Resilio Sync looks like it would definitely do the job! Thank you, and great work on the plugin boroda
For my particular use case, I realized I don't need Sync Links though (i.e. I was actually already using the option to "preserve folder and file names"). So I instead configured MusicBee to automatically export the playlists to the same path relative to my root music folder; that way the relative path will be the same when it gets to my Android device. Setting up Resilio Sync also worked great and it was pretty straightforward following their instructions. If the majority of your files are already synced, just turn on the advanced options so that you can sync to an existing folder on your phone.
Thank you again!Important note of caution:
I'm not sure what exactly caused it, but when I first realized I don't need Sync Links I decided to uninstall it. When I did, MusicBee popped up an error and all of my music files got deleted (except for 2 random songs for some reason). Resilio was also in the middle of indexing my music at the time, so that could have been related. I was panicking at the time so I closed the error output without thinking... but it turned out ok for me since all of my music was actually on my sd card already.