Hi @BigJay2100 ,
Please first understand under Outlook tag, we mainly focus on general issues about Outlook desktop client, I have researched and tested a lot about your issue. As I know, the search folder function is available to outlook desktop client but not for owa, here is a relevant thread, for your reference:
Full Unread Folder for Outlook OWA : Where is it?
In this case, I'm afraid we could only search all folder via "isread:no" or filter the folder manually via "Unread" to meet it in owa now. If you still need this feature in owa, it's recommended to submit a feedback in owa like below (click the "?" icon>feedback>I have a suggestion), your time and effort would be highly appreciated and would benefit Microsoft improve the product in the future.
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