With Google Workspace on GCP and Vaultastic on AWS, will the email data be archived across cloud providers?

Yes, configuring Vaultastic for mail domains hosted on cloud services like Google Workspace ensures that a physical copy of every email sent and received is securely archived to Vaultastic on the AWS cloud. 

This multi-cloud strategy reduces the risk of vendor lock-in by allowing you to maintain control of your most critical data in an independent infrastructure. Additionally, Vaultastic optimizes information archiving costs by up to 60% using multiple strategies such as de-duplication, compression, automation and storage tiering.