
Hi @Azure Admin Alison Slater ,
Welcome to Q&A forum!
According to your description, there is no OOTB way to achieve your needs, unless you use development methods to customize. Since you will eventually migrate to SharePoint Online, I suggest that during the transition period of migration, you can directly create M365 accounts for all users and give them appropriate permissions to SharePoint Online, so that they can also search for the migrated content in SharePoint Online, and try not to affect their work. Then you can complete the migration as soon as possible. This should help you get through the transition period of migration smoothly.
Please do let us know if you have any further queries.
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