The normal process of AO is to create the PO, Receive, and Sync the bill
from AO to QB at the end of the process. Therefore, the PO will not
sync to QB, it will sync only after it is received and billed.
To set AO to sync the PO from AO to QB: Go to the menu Company,
Preferences, and QB Synchronization. Click on the PO/Receiving and
uncheck Block all POs from being sent to QB. This will allow you to
sync the PO from AO to QB.
***However, note that when you sync the PO to QB, the PO in AO will be
closed. When you receive the PO in QB there is no way to sync the
transaction back to AO.