SELECT 
  * 
FROM 
  tconnect_wk_push_notification_settings 
  LEFT JOIN tconnect_wk_push_notification_settings_descriptions ON tconnect_wk_push_notification_settings.setting_id = tconnect_wk_push_notification_settings_descriptions.setting_id 
  AND tconnect_wk_push_notification_settings_descriptions.lang_code = 'en'

Query time 0.00103

JSON explain

{
  "query_block": {
    "select_id": 1,
    "nested_loop": [
      {
        "table": {
          "table_name": "tconnect_wk_push_notification_settings",
          "access_type": "system",
          "rows": 0,
          "filtered": 0,
          "const_row_not_found": true
        }
      },
      {
        "table": {
          "table_name": "tconnect_wk_push_notification_settings_descriptions",
          "access_type": "system",
          "rows": 0,
          "filtered": 0,
          "const_row_not_found": true
        }
      }
    ]
  }
}