SELECT 
  cscart_payments.payment_id, 
  cscart_payment_descriptions.payment 
FROM 
  cscart_payments 
  LEFT JOIN cscart_payment_descriptions ON cscart_payment_descriptions.payment_id = cscart_payments.payment_id 
WHERE 
  cscart_payments.cp_rest_def = 'Y' 
  AND cscart_payments.status = 'A' 
  AND cscart_payment_descriptions.lang_code = 'en' 
  AND cscart_payments.payment_id NOT IN ('')

Query time 0.00047

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "table_name": "cscart_payment_descriptions",
      "access_type": "ALL",
      "possible_keys": ["PRIMARY"],
      "rows": 14,
      "filtered": 78.571,
      "attached_condition": "cscart_payment_descriptions.lang_code = 'en'"
    },
    "table": {
      "table_name": "cscart_payments",
      "access_type": "eq_ref",
      "possible_keys": ["PRIMARY"],
      "key": "PRIMARY",
      "key_length": "3",
      "used_key_parts": ["payment_id"],
      "ref": ["herbaria_cscart_4_18.cscart_payment_descriptions.payment_id"],
      "rows": 1,
      "filtered": 100,
      "index_condition": "cscart_payments.payment_id <> ''",
      "attached_condition": "cscart_payments.cp_rest_def = 'Y' and cscart_payments.`status` = 'A'"
    }
  }
}