SELECT 
  lang.value 
FROM 
  cscart_language_values lang 
WHERE 
  lang.lang_code = 'en' 
  AND lang.name = 'state_field_required_only_for_countries_with_regions'

Query time 0.00062

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "1.00"
    },
    "table": {
      "table_name": "lang",
      "access_type": "const",
      "possible_keys": [
        "PRIMARY"
      ],
      "key": "PRIMARY",
      "used_key_parts": [
        "lang_code",
        "name"
      ],
      "key_length": "392",
      "ref": [
        "const",
        "const"
      ],
      "rows_examined_per_scan": 1,
      "rows_produced_per_join": 1,
      "filtered": "100.00",
      "cost_info": {
        "read_cost": "0.00",
        "eval_cost": "0.20",
        "prefix_cost": "0.00",
        "data_read_per_join": "408"
      },
      "used_columns": [
        "lang_code",
        "name",
        "value"
      ]
    }
  }
}

Result

value
The "State" field is required for all countries with states or provinces. If you don't have states for the customer's country, then the field will be required at checkout only if it is required in the customer's profile.