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 = 7228 
WHERE 
  cscart_products_categories.product_id IN (
    99891, 99892, 99893, 99894, 99895, 99896, 
    99897, 99898, 99899, 99900, 99901, 
    99902, 99903, 99904, 99905, 99906, 
    99907, 99908, 99909, 99910, 99911, 
    99912, 99913, 99914, 99915, 99916, 
    99917, 99918, 99919, 99920, 99921, 
    99922, 99923, 99924, 99925, 99926, 
    99927, 99928, 99929, 99930, 99931, 
    99932, 99933, 99934, 99935, 99936, 
    99937, 99938
  ) 
GROUP BY 
  cscart_products_categories.product_id

Query time 0.00143

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "43.48"
    },
    "grouping_operation": {
      "using_filesort": false,
      "nested_loop": [
        {
          "table": {
            "table_name": "cscart_products_categories",
            "access_type": "range",
            "possible_keys": [
              "PRIMARY",
              "link_type",
              "pt"
            ],
            "key": "pt",
            "used_key_parts": [
              "product_id"
            ],
            "key_length": "3",
            "rows_examined_per_scan": 48,
            "rows_produced_per_join": 48,
            "filtered": "100.00",
            "using_index": true,
            "cost_info": {
              "read_cost": "5.08",
              "eval_cost": "4.80",
              "prefix_cost": "9.88",
              "data_read_per_join": "768"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "link_type"
            ],
            "attached_condition": "(`nuie_scalesta_net`.`cscart_products_categories`.`product_id` in (99891,99892,99893,99894,99895,99896,99897,99898,99899,99900,99901,99902,99903,99904,99905,99906,99907,99908,99909,99910,99911,99912,99913,99914,99915,99916,99917,99918,99919,99920,99921,99922,99923,99924,99925,99926,99927,99928,99929,99930,99931,99932,99933,99934,99935,99936,99937,99938))"
          }
        },
        {
          "table": {
            "table_name": "product_position_source",
            "access_type": "eq_ref",
            "possible_keys": [
              "PRIMARY",
              "pt"
            ],
            "key": "PRIMARY",
            "used_key_parts": [
              "category_id",
              "product_id"
            ],
            "key_length": "6",
            "ref": [
              "const",
              "nuie_scalesta_net.cscart_products_categories.product_id"
            ],
            "rows_examined_per_scan": 1,
            "rows_produced_per_join": 48,
            "filtered": "100.00",
            "cost_info": {
              "read_cost": "12.00",
              "eval_cost": "4.80",
              "prefix_cost": "26.68",
              "data_read_per_join": "768"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "position"
            ]
          }
        },
        {
          "table": {
            "table_name": "cscart_categories",
            "access_type": "eq_ref",
            "possible_keys": [
              "PRIMARY",
              "c_status",
              "p_category_id"
            ],
            "key": "PRIMARY",
            "used_key_parts": [
              "category_id"
            ],
            "key_length": "3",
            "ref": [
              "nuie_scalesta_net.cscart_products_categories.category_id"
            ],
            "rows_examined_per_scan": 1,
            "rows_produced_per_join": 2,
            "filtered": "5.00",
            "cost_info": {
              "read_cost": "12.00",
              "eval_cost": "0.24",
              "prefix_cost": "43.48",
              "data_read_per_join": "6K"
            },
            "used_columns": [
              "category_id",
              "usergroup_ids",
              "status",
              "storefront_id"
            ],
            "attached_condition": "((`nuie_scalesta_net`.`cscart_categories`.`storefront_id` in (0,1)) and ((`nuie_scalesta_net`.`cscart_categories`.`usergroup_ids` = '') or (0 <> find_in_set(0,`nuie_scalesta_net`.`cscart_categories`.`usergroup_ids`)) or (0 <> find_in_set(1,`nuie_scalesta_net`.`cscart_categories`.`usergroup_ids`))) and (`nuie_scalesta_net`.`cscart_categories`.`status` in ('A','H')))"
          }
        }
      ]
    }
  }
}

Result

product_id category_ids position
99891 7229M
99892 7229M
99893 7234M
99894 7234M
99895 7231M
99896 7231M
99897 7234M
99898 7234M
99899 7231M
99900 7231M
99901 7234M
99902 7234M
99903 7231M
99904 7231M
99905 7234M
99906 7234M
99907 7231M
99908 7231M
99909 7234M
99910 7234M
99911 7231M
99912 7231M
99913 7234M
99914 7234M
99915 7231M
99916 7231M
99917 7234M
99918 7234M
99919 7229M
99920 7229M
99921 7229M
99922 7229M
99923 7229M
99924 7229M
99925 7229M
99926 7229M
99927 7229M
99928 7229M
99929 7229M
99930 7229M
99931 7229M
99932 7234M
99933 7231M
99934 7234M
99935 7231M
99936 7231M
99937 7231M
99938 7234M