There is no official method to migrate Google groups to M365. And according to the official document you mentioned, we could only migrate the followings:
- Mail & Rules
- Calendar
- Contacts
Based on my experience, the easiest way to import distribution groups in bulk is to create distribution groups in bulk and then add members in bulk.
You can refer to this article for action: https://blog.jijitechnologies.com/add-members-to-distribution-group-by-csv-using-powershell
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