Google introduced a simplified cross-region replication capability for Cloud SQL customers.
The capability allows applications and databases to quickly restart service in another available region if a Google Cloud region fails.
Cloud SQL cross-region replication, which is available for MySQL and PostgreSQL database engines, simplifies the creation of a fully managed read replica in a different region than that of the primary instance.
https://cloud.google.com/blog/products/databases/introducing-cross-region-replica-for-cloud-sql