Sandbox

SELECT 
  a.modifier, 
  a.modifier_type, 
  IF(
    shared_option_variants.variant_id IS NOT NULL, 
    shared_option_variants.modifier, 
    a.modifier
  ) as modifier, 
  IF(
    shared_option_variants.variant_id IS NOT NULL, 
    shared_option_variants.modifier_type, 
    a.modifier_type
  ) as modifier_type, 
  a.variant_id 
FROM 
  cscart_product_option_variants a 
  LEFT JOIN cscart_ult_product_option_variants shared_option_variants ON shared_option_variants.variant_id = a.variant_id 
  AND shared_option_variants.company_id = 1 
WHERE 
  1 
  AND a.variant_id IN (
    218911, 220126, 220140, 220171, 220191, 
    220190, 220199, 220236, 220257, 220256, 
    220255, 220286, 220414, 220285, 220287, 
    220289, 220288, 220301, 220302, 220296, 
    220318
  )

Query time 0.00081

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "table_name": "shared_option_variants",
      "access_type": "system",
      "possible_keys": ["PRIMARY", "company_id"],
      "rows": 0,
      "filtered": 0,
      "const_row_not_found": true
    },
    "table": {
      "table_name": "a",
      "access_type": "range",
      "possible_keys": ["PRIMARY"],
      "key": "PRIMARY",
      "key_length": "3",
      "used_key_parts": ["variant_id"],
      "rows": 21,
      "filtered": 100,
      "attached_condition": "a.variant_id in (218911,220126,220140,220171,220191,220190,220199,220236,220257,220256,220255,220286,220414,220285,220287,220289,220288,220301,220302,220296,220318)"
    }
  }
}

Result

modifier	modifier_type	variant_id
0.000	A	218911
0.000	A	220126
0.000	A	220140
0.000	A	220171
0.000	A	220190
0.000	A	220191
0.000	A	220199
0.000	A	220236
0.000	A	220255
0.000	A	220256
0.000	A	220257
0.000	A	220285
0.000	A	220286
0.000	A	220287
0.000	A	220288
0.000	A	220289
0.000	A	220296
0.000	A	220301
0.000	A	220302
0.000	A	220318
0.000	A	220414