Need to create a rule in WSS portal policy which will redirect specific traffic to desired URL.
E.g. Traffic destined for "example.com" needs to go to "test.example.com"
WSS Portal based policy
This can be achieved by creating in Group B of the Content Filtering policy in WSS portal. Please use "Redirect" verdict option in order to provide redirection URL in the rule.
Please use below screenshot for a reference -
You can enter the URL of your choice in Destination Condition and Verdict section of your rule as per requirement.