SELECT 
  1 
FROM 
  information_schema.statistics 
WHERE 
  table_schema = DATABASE() 
  AND table_name = 'cscart_cities' 
  AND index_name = 'cs' 
LIMIT 
  1

Query time 0.00027

JSON explain

{
  "query_block": {
    "select_id": 1,
    "nested_loop": [
      {
        "table": {
          "table_name": "statistics",
          "access_type": "ALL",
          "key": "TABLE_SCHEMA,TABLE_NAME",
          "attached_condition": "information_schema.statistics.TABLE_SCHEMA = 'demov2026' and information_schema.statistics.`TABLE_NAME` = 'cscart_cities' and information_schema.statistics.INDEX_NAME = 'cs'",
          "open_frm_only": true,
          "scanned_databases": 0
        }
      }
    ]
  }
}