How to encrypt exFAT on external drive? I have a lot of data on my external drive.
The file system is the exFAT.
I believe it is not possible to encrypt that filesystem with FileVault.

Do you know how (tool maybe) to encrypt exFAT on an external drive without changing filesystem?
I confirm that drives that use the FAT or the exFAT file format can’t be encrypted using FileVault. 

Therefore, if this can help, I suggest you to create two partitions of the device using two different file format.