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 (
    217615, 220113, 220134, 240507, 240536, 
    240559, 240582, 220225, 220226, 220233, 
    220250, 220248, 220249, 220273, 220274, 
    220275, 220276, 220277, 220279, 220318
  )

Query time 0.00044

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": 20,
      "filtered": 100,
      "attached_condition": "a.variant_id in (217615,220113,220134,240507,240536,240559,240582,220225,220226,220233,220250,220248,220249,220273,220274,220275,220276,220277,220279,220318)"
    }
  }
}

Result

modifier	modifier_type	variant_id
0.000	A	217615
0.000	A	220113
0.000	A	220134
0.000	A	220225
0.000	A	220226
0.000	A	220233
0.000	A	220248
0.000	A	220249
0.000	A	220250
0.000	A	220273
0.000	A	220274
0.000	A	220275
0.000	A	220276
0.000	A	220277
0.000	A	220279
0.000	A	220318
0.000	A	240507
0.000	A	240536
0.000	A	240559
0.000	A	240582