Hi @Jim Milagrosa,
There is no recommended approach for bulk decrypting AD RMS-protected documents for migration from SharePoint 2010 to SharePoint Online. However, you can use the Azure Information Protection migration tool to migrate AD RMS-protected documents to Azure Information Protection. After migration, you can decrypt the documents using Azure Information Protection.
Please take a reference to this article: Migrating from AD RMS to Azure Information Protection.
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