Encrypt Documents folder without using Filevault in Catalina I have a 2012 Mac Mini running Catalina (10.15.7) that has been suffering Bluetooth issues for the last month or so leading me to try most things on the Internet that I could find to fix a disconnecting keyboard / mouse  and crackling sound.
The Mini has one SSD (boot and user space - APFS) and one HDD (old, clunky, Journaled / Encrypted) for file backups and odd files.  I do not really want to move the whole Documents folder here (some of the VMs really suffer on the tin disk) so the using System Prefs to move the home folders article may not be a solution in my case.
After many frustrating days, I found a note that Filevault could be the issue and in my case turning this off does seem to have solved my drops over the lat few days but at the cost of leaving my main data unencrypted if the disk is removed from the Mac (user and disk passwords are complex but still an acknowledged weak point in this).
For most of my files this is not an issue but for others (work related / bank etc) this is not good practise and kind of goes against my instincts.  The only way around this I could think of is:

Encrypt the second disk in the Mac using 'Mac OS Extended' format rather than APFS
Create a symbolic link in Documents to a folder on this encrypted disk
Store any 'sensitive' documents in here but away from the normal folder structure.

I did wonder about using VeraCrypt but never used it and could not work out if I could encrypt the Documents folder or hard disk as most fo the instructions are for Windows.
Can anyone think of another way?
I like making an encrypted disk image to store documents. Step 6 covers the choice of encryption. The guide has a selector at the top for Catalina version of macOS.

https://support.apple.com/guide/disk-utility/create-a-disk-image-dskutl11888/mac

If you’re not sure which type of image, I recommend starting with a sparse image and avoiding sparse bundle or Read+Write.