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 = 22 
WHERE 
  cscart_products_categories.product_id IN (
    104659, 104658, 104657, 104656, 104655, 
    105977, 105976, 105975, 104560, 104559, 
    104558, 104557, 104556, 104555, 104529, 
    104573, 104572, 104571, 104505, 104504
  ) 
GROUP BY 
  cscart_products_categories.product_id

Query time 0.00046

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE cscart_products_categories range PRIMARY,pt pt 3 21 Using where; Using index
1 SIMPLE cscart_categories eq_ref PRIMARY,c_status,p_category_id PRIMARY 3 toolboxdigitalshop_dev.cscart_products_categories.category_id 1 Using where
1 SIMPLE product_position_source eq_ref PRIMARY,pt PRIMARY 6 const,toolboxdigitalshop_dev.cscart_products_categories.product_id 1

Result

product_id category_ids position
104504 22M 0
104505 22M 0
104529 33,22M 0
104555 22M 0
104556 22M 0
104557 22M 0
104558 22M 0
104559 22M 0
104560 22M 0
104571 22M 0
104572 22M 0
104573 22M 0
104655 22M 0
104656 22M 0
104657 22M 0
104658 22M 0
104659 22M 0
105975 22M 0
105976 22M 0
105977 22M 0