As of Cloud Foundation version 4.1, the edge cluster automation capabilities of the SDDC manager does not include the ability to remove a previously deployed Edge Cluster. To fill this gap, VMware provides a separate "edge cleaner" tool as part of the VMware Knowledge Base Article: https://kb.vmware.com/s/article/78635.
This post will look at the edge cleaner tool and how it is used to remove previously deployed NSX Edge Clusters from a Cloud Foundation domain