FOX - Currency Switcher Professional for WooCommerce

WPML:

• open functions.php of your current wp theme
• drop there next PHP code:

  add_filter('wp_head', function() {
      $lang = ICL_LANGUAGE_CODE;
      global $WOOCS;
      switch ($lang)
      {
          case 'bg':
              $WOOCS->set_currency('BGN');
              break;
          case 'en':
              $WOOCS->set_currency('EUR');
              break;
          default:
              $WOOCS->set_currency('USD');
              break;
      }
  });

• See WPML docs about languages codes

Polylang and TranslatePress:

• open functions.php of your current wp theme
• drop there next PHP code:

  add_filter('wp_head', function() {
      $lang = get_locale();
      global $WOOCS;
      switch ($lang)
      {
          case 'bg_BG':
              $WOOCS->set_currency('BGN');
              break;
          case 'en_GB':
              $WOOCS->set_currency('EUR');
              break;
          default:
              $WOOCS->set_currency('USD');
              break;
      }
  });

• https://wordpress.org/support/topic/switch-currency-with-language-change-polylang/
• See Polylang docs about languages codes

GTranslate:

• open functions.php of your current wp theme
• drop there next PHP code:

  add_filter('wp_head', function() {
      $lang = isset($_SERVER['HTTP_X_GT_LANG']) ? $_SERVER['HTTP_X_GT_LANG'] : '';
      global $WOOCS;
      switch ($lang)
      {
          case 'bg_BG':
              $WOOCS->set_currency('BGN');
              break;
          case 'en_GB':
              $WOOCS->set_currency('EUR');
              break;
          default:
              $WOOCS->set_currency('USD');
              break;
      }
  });

• https://wordpress.org/plugins/gtranslate/

qTranslate X integration:

• open functions.php of your current wp theme
• drop there next PHP code:

  add_action('wp_head', function () {
      if (function_exists('qtranxf_getLanguage') AND class_exists('WOOCS')) {
          $lang = qtranxf_getLanguage();
          global $WOOCS;
          switch ($lang) {
              case 'bg': $WOOCS->set_currency('BGN');
                  break;
              case 'en': $WOOCS->set_currency('EUR');
                  break;
              default: $WOOCS->set_currency('USD');
                  break;
          }
      }
  });