Compression is only done during the backup. 2.9 has that as default now.
See:
https://docs.moodle.org/29/en/File_system_repository
The only way to avoid download from one Moodle server and then upload to another is to have command line access on the server where the backup is being made.
Run the backup.php script in moodlecode/admin/cli/ and point that script to a directory to which you have shell access ... something like /home/ken/
Then, ssh into the server where the backup was made and go to the directory where the backup was saved. scp the .mbz file to the other server's file system repository.
If on the same server ... ie, backing up a course to restore to a new course on same server, the process is similar. Run backup php script with the destination to the file system repository setup for the server.
One can then simply setup the file system repo in any course and then use restore there to restore the course.
Uploading/Downloading files can present some problems ... timings on scripts, upload size in not only PHP but Apache + any restrictions the hosting provider might impose depending upon the package purchased.
'spirit of sharing', Ken