How to Restrict POs based on additional parameters such as 'PO Creation Source' or 'Buyer Name' etc

Hi

We have a below requirement.

Under same BU,

• Some POs are created from an external source . (we are using a separate buyer E.g 'Integration Buyer' to create these POs)- And these are maintained by some set of buyers once they arrive fusion (Lets say Buyer A)

• Some POs are created and maintained by a different set of buyers. (Lets say Buyer B)

We don not want 'Buyer A' to view and close POs of 'Buyer B'.

If we try to set up Procurement agent» Manage Purchase orders> view other agent documents = None, 'Buyer A' can not access integration POs at all as the buyer on these POs is an 'Integration user'