SELECT 
  b.variant_name, 
  a.*, 
  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 
FROM 
  cscart_product_option_variants AS a 
  LEFT JOIN cscart_product_option_variants_descriptions AS b ON b.variant_id = a.variant_id 
  AND b.lang_code = 'en' 
  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.option_id IN (2) 
  AND a.status = 'A' 
ORDER BY 
  a.position, 
  a.variant_id

Query time 0.00057

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost": 0.01801512,
    "nested_loop": [
      {
        "read_sorted_file": {
          "filesort": {
            "sort_key": "a.position, a.variant_id",
            "table": {
              "table_name": "a",
              "access_type": "ref",
              "possible_keys": ["status", "option_id", "option_id_2"],
              "key": "option_id",
              "key_length": "6",
              "used_key_parts": ["option_id", "status"],
              "ref": ["const", "const"],
              "loops": 1,
              "rows": 5,
              "cost": 0.00743232,
              "filtered": 100,
              "index_condition": "a.`status` = 'A'",
              "attached_condition": "a.option_id <=> 2 and a.`status` <=> 'A'"
            }
          }
        }
      },
      {
        "table": {
          "table_name": "b",
          "access_type": "eq_ref",
          "possible_keys": ["PRIMARY"],
          "key": "PRIMARY",
          "key_length": "9",
          "used_key_parts": ["variant_id", "lang_code"],
          "ref": ["lvshop.a.variant_id", "const"],
          "loops": 5,
          "rows": 1,
          "cost": 0.0052914,
          "filtered": 100,
          "attached_condition": "trigcond(b.lang_code = 'en')"
        }
      },
      {
        "table": {
          "table_name": "shared_option_variants",
          "access_type": "eq_ref",
          "possible_keys": ["PRIMARY", "company_id"],
          "key": "PRIMARY",
          "key_length": "7",
          "used_key_parts": ["variant_id", "company_id"],
          "ref": ["lvshop.a.variant_id", "const"],
          "loops": 5,
          "rows": 1,
          "cost": 0.0052914,
          "filtered": 100
        }
      }
    ]
  }
}