Replicate the below catalogs from the patch channel onto the ZENworks server:
OES2018-SP3-Pool
OES2018-SP3-Updates
OES2018-SP3-SLES12-SP5-Pool
OES2018-SP3-SLES12-SP5-Updates
OES2018-SP3-SLE-Module-Containers12-Pool
OES2018-SP3-SLE-Module-Containers12-Updates
For more information on creating and replicating subscriptions, see Section II, Subscriptions. After replication, assign the bundles to the OES 2018 SP2 server.