Hi @Ale Madama ,
Welcome to our forum!
Based on my test on dragging and dropping emails out of Outlook, i found that the original date of the emails will not be retained, only the time the message was moved to the folder, which is consistent with your issue. It's by design.
As a workaround, it's suggested that you could that you could try to export the emails to a .pst file. In this way, the emails will be opened in Outlook, and all the original information of the messages including the date will be stored.
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