SELECT 
  cscart_settings_variants.*, 
  cscart_settings_descriptions.value, 
  cscart_settings_descriptions.object_type 
FROM 
  cscart_settings_variants 
  INNER JOIN cscart_settings_descriptions ON cscart_settings_descriptions.object_id = cscart_settings_variants.variant_id 
  AND object_type = 'V' 
WHERE 
  cscart_settings_variants.object_id = 56 
  AND cscart_settings_descriptions.lang_code = 'en' 
ORDER BY 
  cscart_settings_variants.position

Query time 0.00048

JSON explain

{
  "query_block": {
    "select_id": 1,
    "read_sorted_file": {
      "filesort": {
        "table": {
          "table_name": "cscart_settings_variants",
          "access_type": "ALL",
          "possible_keys": ["PRIMARY"],
          "rows": 404,
          "filtered": 100,
          "attached_condition": "(cscart_settings_variants.object_id = 56)"
        }
      }
    },
    "table": {
      "table_name": "cscart_settings_descriptions",
      "access_type": "eq_ref",
      "possible_keys": ["PRIMARY"],
      "key": "PRIMARY",
      "key_length": "14",
      "used_key_parts": ["object_id", "object_type", "lang_code"],
      "ref": [
        "egkcysbp_cscartn.cscart_settings_variants.variant_id",
        "const",
        "const"
      ],
      "rows": 1,
      "filtered": 100,
      "index_condition": "((cscart_settings_descriptions.lang_code = 'en') and (cscart_settings_descriptions.object_type = 'V'))"
    }
  }
}