SELECT 
  tmall_products_categories.product_id, 
  GROUP_CONCAT(
    IF(
      tmall_products_categories.link_type = "M", 
      CONCAT(
        tmall_products_categories.category_id, 
        "M"
      ), 
      tmall_products_categories.category_id
    )
  ) AS category_ids 
FROM 
  tmall_products_categories 
  INNER JOIN tmall_categories ON tmall_categories.category_id = tmall_products_categories.category_id 
  AND tmall_categories.storefront_id IN (0, 1) 
  AND (
    tmall_categories.usergroup_ids = '' 
    OR FIND_IN_SET(
      0, tmall_categories.usergroup_ids
    ) 
    OR FIND_IN_SET(
      1, tmall_categories.usergroup_ids
    )
  ) 
  AND tmall_categories.status IN ('A', 'H') 
WHERE 
  tmall_products_categories.product_id IN (
    278, 280, 282, 247, 248, 241, 244, 245, 
    246, 240, 6, 66, 166, 214, 219, 221, 223, 
    192, 194, 195
  ) 
GROUP BY 
  tmall_products_categories.product_id

Query time 0.01035

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost": 0.092136833,
    "nested_loop": [
      {
        "table": {
          "table_name": "tmall_products_categories",
          "access_type": "range",
          "possible_keys": ["PRIMARY", "pt"],
          "key": "pt",
          "key_length": "3",
          "used_key_parts": ["product_id"],
          "loops": 1,
          "rows": 22,
          "cost": 0.0398197,
          "filtered": 100,
          "index_condition": "tmall_products_categories.product_id in (278,280,282,247,248,241,244,245,246,240,6,66,166,214,219,221,223,192,194,195)"
        }
      },
      {
        "table": {
          "table_name": "tmall_categories",
          "access_type": "eq_ref",
          "possible_keys": ["PRIMARY", "c_status", "p_category_id"],
          "key": "PRIMARY",
          "key_length": "3",
          "used_key_parts": ["category_id"],
          "ref": ["tmall.tmall_products_categories.category_id"],
          "loops": 22,
          "rows": 1,
          "cost": 0.038243372,
          "filtered": 100,
          "attached_condition": "tmall_categories.storefront_id in (0,1) and (tmall_categories.usergroup_ids = '' or find_in_set(0,tmall_categories.usergroup_ids) or find_in_set(1,tmall_categories.usergroup_ids)) and tmall_categories.`status` in ('A','H')"
        }
      }
    ]
  }
}

Result

product_id category_ids
6 191M
66 189M
166 199,198M
192 232M
194 232M
195 232M
214 168M
219 169M
221 169M
223 165M
240 165M
241 165M
244 168M
245 235M
246 199M
247 165M
248 255,248M
278 224M
280 224M
282 224M