The SymplySPARK is shipped as standard since June 2022 with the APFS Format. The Spark does support APFS Encryption, but the storage would need to be reformatted.
For more information on how to Encrypt volumes using the macOS Disk Utility click [here]
For more information on File System formats available for the macOS click [here]
If you have any questions please submit a [support ticket]