ACF Load layouts into flex field

load.php

<?php
add_filter( 'acf/load_field/name=flex_layout', __CLASS__ . '::craft_content_layouts' );

static function craft_content_layouts( $field ) {

  // Remove the layouts
  // that are named in this list
  $remove_list = [
    'paragraph',
    'banner',
  ];
  foreach ( $field['layouts'] as $i => $layout ) {
    if ( in_array( $layout['name'], $remove_list ) ) {
      unset( $field['layouts'][ $i ] );
    }
  }

  /**
   * Load another AC Flex field into this layout mix
   */
  // $additional_fields = acf_get_fields( 'additional_flex_field' );
  // foreach ($additional_fields['layouts'] as $layout) {
  //  $field['layouts'][] = $layout;
  // }
  return $field;
} );