RESOLUTION
To do this follow the steps below (for examaple migration from Plesk):
1. Upload appropriate migration agent (for Plesk it is /usr/local/psa/PMM/PleskX.pl) to the source server.
2. Run it with --help option to get information how to use this script.
3. Then copy the files from ./pma directory from the source server to /usr/local/psa/PMM/archives on the destination Plesk.
4. Copy PleskX.xml to /usr/local/psa/PMM/var on the destination server and rename it to dump.xml.
5. Then you can migrate data via Plesk on Server->Migration page in "Import mode".