Wich Plugin to generate Custom Post Types works best with ACF?

A very simple solution

create your very own highly custom post types that work perfectly with ACF without needing any plugin.

Put this in your template’s functions.php file

Just change the labels to what you need and you are good to go

add_action( 'init', 'create_clients' );
function create_clients() {
	 $labels = array(
    'name' => _x('Clients', 'post type general name'),
    'singular_name' => _x('Client', 'post type singular name'),
    'add_new' => _x('Add New', 'Client'),
    'add_new_item' => __('Add new Client'),
    'edit_item' => __('Edit client'),
    'new_item' => __('New client'),
    'view_item' => __('View client'),
    'search_items' => __('Search clients'),
    'not_found' =>  __('No clients found'),
    'not_found_in_trash' => __('No clients found in Trash'),
    'parent_item_colon' => ''
  );

  $supports = array('title',  'page-attributes');

  register_post_type( 'clients',
    array(
      'labels' => $labels,
      'public' => true,
      'supports' => $supports,
      'hierarchical' => true
    )
  );
}

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I would definitely say Custom Post Type UI.

But as I experienced it, using register_post_type is always trouble free since there is always some annoyances with some missing or buggy plugin functionalities.