SELECT 
  * 
FROM 
  cscart_product_feature_variants 
WHERE 
  variant_id IN (
    4793, 4786, 4764, 4790, 3953, 4792, 4777, 
    4778, 4766, 4783, 4773, 4799, 4779, 
    4810, 4776, 4780, 4806, 4782, 4784, 
    4797, 3745, 3719, 1938, 3709, 4754, 
    4862, 1978, 1934, 4753, 4867, 1912, 
    1895, 1858, 1862, 4755, 4879, 5162, 
    1939, 2970, 1987, 1970, 1941, 5137, 
    2144, 1870, 1859, 0
  )

Query time 0.00065

JSON explain

{
  "query_block": {
    "select_id": 1,
    "nested_loop": [
      {
        "table": {
          "table_name": "cscart_product_feature_variants",
          "access_type": "range",
          "possible_keys": ["PRIMARY"],
          "key": "PRIMARY",
          "key_length": "3",
          "used_key_parts": ["variant_id"],
          "rows": 47,
          "filtered": 100,
          "index_condition": "cscart_product_feature_variants.variant_id in (4793,4786,4764,4790,3953,4792,4777,4778,4766,4783,4773,4799,4779,4810,4776,4780,4806,4782,4784,4797,3745,3719,1938,3709,4754,4862,1978,1934,4753,4867,1912,1895,1858,1862,4755,4879,5162,1939,2970,1987,1970,1941,5137,2144,1870,1859,0)"
        }
      }
    ]
  }
}