The following  In-Place Archive features require specific Outlook licenses and either a Microsoft Exchange Online account or a Microsoft Exchange Server License with a Microsoft Exchange Server Client License (CAL): 

If after placing retention policy in a user from the Global admin side all the mails go into the archive folder if the user is not able to see his/her mails on the outlook client but able to see the in-place archive in OWA.

Inplace archive in Outlook client.

Inplace archive in Outlook Web App.

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Show if the user is not able to see the In-place archive in Outlook client it might be the issue of the product installed as not all product show folder for In-place archive 

List of the product which shows In place archive are:-

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