Hi @Sackey ,
Welcome to our forum!
According to your description, i understand the "'Important/priority messages' and 'Others' (in french, it is called Prioritaire and Autre" you mentioned is Focused Inbox for Outlook and you want to create a rule only for emails in Focused tab. I'm afraid that it's not available in Outlook to create rules only for emails in Focused tab.
As i know, we can only use inbox rules to automatically perform specific actions on email that arrives in your Inbox. But both Focused and Other tab are in Inbox, so we cannot isolate them or add condition only about Focused tab in a rule.
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