Currently Unsubscribe button are available for the marketing emails. And for that you will need a license I guess.
If needed you can create your own Unsubscribe link where on click of it will just draft an email and sent to your mailbox. Once it is received you can check subject and then make that contacts settings as Unsubscribed.
If possible can you explain your requirement with some more details ? Like what are emails? Are this from outside of your organization and sent to your user?
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