This gits is just for sharing my experience so it might not be the best fit for you. But I hope this might help someone facing similar problems in the future.
Our team had to shutdown one of the clusters in GKE but there were some development dependencies to our nexus repository which is exposed as URI. So the team decided to migrate entire nexus repository from one GCP project to another and simply change the ip address of the DNS.
While it was easy to migrate the nexus because it was simply deployed as a pod, but it seemed quite difficult the persistent volume it depends upon.