ansible-role-ssh_host_key/tasks/local.yml

---

- name: write local ssh_known_hosts file
  local_action: known_hosts
  args:
    path: "{{ lookup('env','HOME') }}/.ssh/known_hosts"
    name: "{{ inventory_hostname }}"
    key: "{{ inventory_hostname }},{{ ssh_host }} ssh-ed25519 {{ ssh_host_key_ed25519_public }}"
  when: ssh_host_key_ed25519_public is defined
  throttle: 1