S3 Cross Region Replication

Scenario:
We have a requirement that data in Nextcloud live in separate geographic locations. We are looking into the idea of using S3 East and West and Cross Region Replication to ensure data availability.

Question:
If Nextcloud is pointing to S3 East as it’s primary storage location and S3 East becomes unavailable, what would be the mechinism to point nextcloud to S3 West bucket? Bucket name will be the same, just different region.

Thanks for any ideas.