"Copy OpenSSH host keys from the primary node" is incorrect

https://docs.gitlab.com/ee/administration/geo/replication/configuration.html#step-2-manually-replicate-the-primary-nodes-ssh-host-keys

Step 3 says scp root@<primary_node_fqdn>:/etc/ssh/ssh_host_*_key* /etc/ssh How it's going to work if we haven't added secondary's public keys to primary? Is this intended to use the user's localhost? but then it should be explained differently