How to merge free and premium version into one with Freemius

freemius-merging-free-premium.php

<?php
  /**
   * Plugin Name: ...
   * Plugin URI:  ...
   * ...
   *
   * @fs_premium_only /path/to/premium/folder/
   */
  // Freemius Init SDK code
  function my_fs() {
      global $my_fs;
  
      if ( ! isset( $my_fs ) ) {
          // Include Freemius SDK.
          require_once dirname(__FILE__) . '/freemius/start.php';
  
          $my_fs = fs_dynamic_init( array(
            ...
          ) );
      }
  
      return $my_fs;
  }
  
  if ( ! my_fs()->is_premium() ) {
    require_once dirname(__FILE__) . 'path/to/free/loader.php';
  }
  if ( my_fs()->is__premium only() ) {
    if ( my_fs()->can_use_premium_code() ) {
      require_once dirname(__FILE__) . 'path/to/premium/loader.php';
    }
  }