SELECT 
  netting_state_descriptions.state 
FROM 
  netting_states 
  LEFT JOIN netting_state_descriptions ON netting_state_descriptions.state_id = netting_states.state_id 
  AND netting_state_descriptions.lang_code = 'en' 
WHERE 
  netting_states.country_code = 'US' 
  AND netting_states.code = 'NC'

Query time 0.00024

JSON explain

{
  "query_block": {
    "select_id": 1,
    "const_condition": "1",
    "nested_loop": [
      {
        "table": {
          "table_name": "netting_states",
          "access_type": "const",
          "possible_keys": ["cs", "code", "country_code"],
          "key": "cs",
          "key_length": "106",
          "used_key_parts": ["country_code", "code"],
          "ref": ["const", "const"],
          "rows": 1,
          "filtered": 100
        }
      },
      {
        "table": {
          "table_name": "netting_state_descriptions",
          "access_type": "const",
          "possible_keys": ["PRIMARY"],
          "key": "PRIMARY",
          "key_length": "9",
          "used_key_parts": ["state_id", "lang_code"],
          "ref": ["const", "const"],
          "rows": 1,
          "filtered": 100
        }
      }
    ]
  }
}