Ansible Failed to set permissions on the temporary

You could try something like this:

- name: private key 
  become: true
  become_user: root
  copy:
    src: /Users/me/Documents/keys/id_rsa
    dest: ~/.ssh/
    owner: unpriv
    group: unpriv
    mode: 0600
    backup: yes

Notice the:

become: true
become_user: root

Check the "become" docs for more info

Try to install ACL on remote host, after that execute ansible script

sudo apt-get install acl