Cross Tenant Migration licensing

Hello,

I'm planning a native cross-tenant migration for several shared mailboxes that have archives enabled. I’m looking to confirm if it is necessary to temporarily convert these to user mailboxes in the source to ensure the archive data migrates successfully. Also, what specific licenses should I assign to the target objects specifically, do I need to provide an Exchange Online Plan 2 plus the Cross-Tenant User Data Migration add-on for each shared mailbox? If anyone has handled archived shared mailboxes recently, I’d appreciate a quick confirmation on the cleanest licensing and conversion steps. 

Thank you in advance ! :)