@Andrew Talbot-Nagy Thank you for reaching out to us, As I understand correctly you want to manage one of the distribution group in Azure AD (want to perform export/import operations on the group).
There are some groups which cant be managed in the Azure portal, Distribution lists and mail-enabled security groups are managed only in Exchange admin center or Microsoft 365 admin center. You must sign in to Exchange admin center or Microsoft 365 admin center to manage these groups.
Same has been documented here - https://learn.microsoft.com/en-us/azure/active-directory/fundamentals/concept-learn-about-groups
If my understanding of the issue is incorrect, feel free to post back or you can send me an email to 'AzCommunity@microsoft.com' with Sub - Attn: Givary and following details in the email body:
Link to this thread/post and we can connect offline and discuss further on this.
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