Step 1) Upload the backup archive by FTP to any path on your server.
Step 2) Import the archive to your local backups: Run PLESK_BACKUP_PASSWORD="yourpassword" plesk sbin pmm-ras --import-file-as-dump --dump-file-specification /path/to/file.tar
with yourpassword = password of your backup archive, /path/to/file.tar = path and filename of the backup archive.