Never used it personally but it is supported. Create a NAS Media service on the source DX computer and point it at a share on the extended drive of the target DX computer when you create the NAS media. Select the NAS Aggregation Option. More info below:

NAS Aggregation ¿ This option is designed for a system where
files are migrated from one File System Manager extended drive
to another File System Manager extended drive, and then from
the second extended drive to tape. This option tells File System
Manager to restrict renames of files and directories that are
moved to Aggregate NAS media. While NAS media typically
allows for such changes, tape media does not. Therefore, renames
are automatically restricted on the second extended drive.
Enforcing the same restrictions on the first extended drive
(through this option) reduces the possibility of creating orphaned
file tags on the first extended drive.