Using cloudformation for setting upp global database and second cluster from existing cluster

Hi, I have the following scenario: I have an existing aurora-postgres db cluster running in eu-north-1 (Stockholm) region. My usecase is now that I need a second replica cluster in another region (eu-central-1) to be able to use services that are not available in eu-north-1. Setting up a global database is possible in the console, however I want to automate, currently using cloudformation. But when I try to add the resource type AWS::RDS::GlobalCluster to the existing cfn deployed in eu-north-1 it gives me error: "Resource type not found".

I have also tried moving out the globalcluster resource to its own cloudformation template, deploying it in eu-central-1 where the resource type seems to exist (no error here). However, when I specify the primary cluster arn it gives me an error "value for engineName should be specified". I've tried to change the primary cluster ARN to the primary cluster identifier instead, but then get "DBCluster xxyyzz not found" - I can imagine this is due to the fact that I deploy in another region than the primary cluster itself.

Is it possible to accomplish what I want with cloudformation, or am I forced to do it manually?

Thank you