SELECT 
  cscart_products_categories.product_id, 
  GROUP_CONCAT(
    IF(
      cscart_products_categories.link_type = "M", 
      CONCAT(
        cscart_products_categories.category_id, 
        "M"
      ), 
      cscart_products_categories.category_id
    )
  ) AS category_ids, 
  product_position_source.position AS position 
FROM 
  cscart_products_categories 
  INNER JOIN cscart_categories ON cscart_categories.category_id = cscart_products_categories.category_id 
  AND cscart_categories.storefront_id IN (0, 1) 
  AND (
    cscart_categories.usergroup_ids = '' 
    OR FIND_IN_SET(
      0, cscart_categories.usergroup_ids
    ) 
    OR FIND_IN_SET(
      1, cscart_categories.usergroup_ids
    )
  ) 
  AND cscart_categories.status IN ('A', 'H') 
  LEFT JOIN cscart_products_categories AS product_position_source ON cscart_products_categories.product_id = product_position_source.product_id 
  AND product_position_source.category_id = 441 
WHERE 
  cscart_products_categories.product_id IN (
    11310, 10203, 9836, 10204, 10899, 6833, 
    10465, 9603, 9235, 9164, 11308, 11312, 
    22273, 13179, 8735, 9055, 21533, 22369, 
    12135, 12130, 7340, 12133, 7008, 7765
  ) 
GROUP BY 
  cscart_products_categories.product_id

Query time 0.00093

JSON explain

{
  "query_block": {
    "select_id": 1,
    "nested_loop": [
      {
        "table": {
          "table_name": "cscart_products_categories",
          "access_type": "range",
          "possible_keys": ["PRIMARY", "pt"],
          "key": "pt",
          "key_length": "3",
          "used_key_parts": ["product_id"],
          "rows": 25,
          "filtered": 100,
          "index_condition": "cscart_products_categories.product_id in (11310,10203,9836,10204,10899,6833,10465,9603,9235,9164,11308,11312,22273,13179,8735,9055,21533,22369,12135,12130,7340,12133,7008,7765)"
        }
      },
      {
        "table": {
          "table_name": "cscart_categories",
          "access_type": "eq_ref",
          "possible_keys": ["PRIMARY", "c_status", "p_category_id"],
          "key": "PRIMARY",
          "key_length": "3",
          "used_key_parts": ["category_id"],
          "ref": ["lillyshop_lillyshop.cscart_products_categories.category_id"],
          "rows": 1,
          "filtered": 100,
          "attached_condition": "cscart_categories.storefront_id in (0,1) and (cscart_categories.usergroup_ids = '' or find_in_set(0,cscart_categories.usergroup_ids) or find_in_set(1,cscart_categories.usergroup_ids)) and cscart_categories.`status` in ('A','H')"
        }
      },
      {
        "table": {
          "table_name": "product_position_source",
          "access_type": "eq_ref",
          "possible_keys": ["PRIMARY", "pt"],
          "key": "PRIMARY",
          "key_length": "6",
          "used_key_parts": ["category_id", "product_id"],
          "ref": [
            "const",
            "lillyshop_lillyshop.cscart_products_categories.product_id"
          ],
          "rows": 1,
          "filtered": 100
        }
      }
    ]
  }
}

Result

product_id category_ids position
6833 513M
7008 513M
7340 442M
7765 513M
8735 442M
9055 442M
9164 575M
9235 854M
9603 694M
9836 513M
10203 513M
10204 513M
10465 694M
10899 513M
11308 575M
11310 513M
11312 575M
12130 442M
12133 442M
12135 442M
13179 442M
21533 442M
22273 442M
22369 442M