As part of the GCP migration, CASB customer's are required to forward (PSG) Proxy SG traffic through WSS or (MWG) McAfee Web Gateway.
Any customer running the Reach Agent would need to switch to the WSSAgent or Proxy-chaining agentless.
For McAfee Web Gateway, specific documentation has not been verified. Use the documents above to see the high level steps for configuration.
The high level tasks are the same.