Microsoft Cloud App Security (MCAS) can integrate with Azure Information Protection to allow automated policy-driven application of Office 365 sensitivity labels to Office documents and PDFs. You can depend on users to apply labels manually as they create documents, but it’s easy for humans to forget to add protection where a computer won’t. You’ll pay extra for MCAS, but it could be worthwhile.
https://office365itpros.com/2019/08/13/mcas-protects-office-365-content/
