SD cards and USB "thumb" drives are handy devices for shuttling data between different machines. Choosing what file system when formatting an SD card or USB stick takes a little thought. FreeBSD supports lots of file systems as third party packages. In some cases, a binary port is not possible because of licensing that doesn't allow distributing binaries. A fresh install of FreeBSD offers UFS and ZFS out of the box. However, these formats aren't easily shared across other platforms. To secure your data, you want it encrypted. In theory, GELI encryption would cover this but again this is not portable to other platforms.
Veracrypt is a very useful, secure and portable way to share USB flash drives and SD cards between multiple computers running different OSs. Instead of formatting a thumb drive as FAT, UFS, ExFAT, NTFS and then harmonize special file system drivers across all platforms, it is much much easier for format the device as a Veracrypt volume. Plug it in, tell Veracrypt to mount it, enter the password, and you're all set. The added benefit is - if your flash device is lost or stolen - the contents are not easily viewed by a stranger. This is also a good way to backup personal files from your desktop, laptop or tablet device.
Create a directory (for example "media") to use as a mount point. Insert your flash drive or SD card. In the example below, it appears as "/dev/da0s1".
To mount your encrypted SD card or flash drive:
$ sudo veracrypt -t -k "" --pim=0 --protect-hidden=no /dev/da0s1 /media
You will be prompted for a password. If the password matches, the drive is mounted. To see your files:
$ ls /media
You can now get to work!
When done, this will unmount the volume:
$ sudo veracrypt -d
To create a new volume ...
More information: Veracrypt