@Jessica Wilkinson For better understating the issue: If server, running on-prem or in Azure?
If the idea is just to migrate the data to blob so it can be accessed from a plugin in SPO (btw. this is very interesting so if you can share more information on that it would be great) any migration tool that support blob will work. You can use AzCopy as 1p tool or Komprise and Data Dynamics Storage X from the 3p selection (as per comparison matrix). Taking the size, any of them should work. If all of this site in small numbers of shares, I suggest looking at AzCopy first as 3p tools might be an overkill.
However, the question is what will happen with the ACLs and file system metadata? They will be lost when migrating to blob storage so they have to be translated to SPO or that plugin. None of the tools I mentioned supports that. And I am not aware of any tool that would support this directly.
If the issue still persist, I wish to engage with you offline for a closer look and provide a quick and specialized assistance, please send an email with subject line “Attn:subm” to AzCommunity[at]Microsoft[dot]com referencing this thread and the Azure subscription ID, I will follow-up with you. Once again, apologies for any inconvenience with this issue.
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