Ansible does not have a out-of-the-box feature which could make possible to run block of tasks in a serial way (the same as you can do with tasks in a playbooks). To owercome this disadvantage you can include the file with serial tasks like this:

- name: Run tasks per node in serial mode
  ansible.builtin.include_tasks: serial_pipe.yml
  with_items: "{{ groups.all }}"
  loop_control:
    loop_var: _host_item
  when: hostvars[_host_item].inventory_hostname == inventory_hostname