MySQL Enterprise Backup 9.1 Release Notes
MySQL Enterprise Backup 9.1.0 supports the MySQL Server 9.1.x series for back up and restore. It is incompatible with other versions of MySQL Server, for which you should use the MySQL Enterprise Backup of the same release number, or consult the MySQL Enterprise Backup manual of the series for more information.
Also see important information in Section 5.4, “Restoring a Backup with a Database Server Upgrade or Downgrade”.