If you need a stress-free way to migrate between Microsoft 365 tenants, MailsDaddy Cross-Tenant Migration Service is worth trying. It securely moves emails, calendars, OneDrive, and even shared mailboxes. The cloud-based platform requires no installation and uses Microsoft’s Graph API for maximum data protection. We were able to map users in bulk and run migrations in batches, which saved time. Delta sync ensured no new emails were left behind after the initial migration.
https://www.mailsdaddy.com/services/cross-tenant-migration.php