Certificate Maps are only available in global location currently. Regional Certificates should be specified directly on TargetHttpsProxy as a list. Please refer to this tutorial for more details: https://cloud.google.com/certificate-manager/docs/depl...

There's a recently-launched feature (in preview) called "per-project DNS authorization" which generates unique validation subdomains, so that your CNAME records don't collide across projects or regions when validating the same domain. You can use it ...