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 (
    101358, 101703, 101984, 101983, 101944, 
    101921, 101842, 101841, 101839, 101838, 
    101837, 101836, 101835, 101834, 101833, 
    101832, 101831, 101830, 101829, 101828
  ) 
GROUP BY 
  cscart_products_categories.product_id

Query time 0.00049

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE cscart_products_categories range PRIMARY,pt pt 3 20 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
101358 22M 0
101703 22M 0
101828 22M 0
101829 22M 0
101830 22M 0
101831 22M 0
101832 22M 0
101833 22M 0
101834 22M 0
101835 22M 0
101836 22M 0
101837 22M 0
101838 22M 0
101839 22M 0
101841 22M 0
101842 22M 0
101921 22M 0
101944 22M 0
101983 22M 0
101984 22M 0