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 = 7217 
WHERE 
  cscart_products_categories.product_id IN (
    91372, 91374, 91371, 91373, 91370, 91381, 
    91383, 91369, 91368, 91379, 91382, 
    91384, 91351, 91353, 91367, 91377, 
    91380, 91349, 91352, 91354, 91378, 
    91347, 91350, 91348, 91361, 91363, 
    91391, 91393, 91362, 91364, 91392, 
    91394, 91359, 91389, 91360, 91357, 
    91387, 91358, 91390, 91388, 96213, 
    96214, 96215, 96216, 96217, 96218, 
    96219, 96220
  ) 
GROUP BY 
  cscart_products_categories.product_id

Query time 0.01906

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "86.69"
    },
    "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": 96,
            "rows_produced_per_join": 96,
            "filtered": "100.00",
            "using_index": true,
            "cost_info": {
              "read_cost": "9.89",
              "eval_cost": "9.60",
              "prefix_cost": "19.49",
              "data_read_per_join": "1K"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "link_type"
            ],
            "attached_condition": "(`nuie_scalesta_net`.`cscart_products_categories`.`product_id` in (91372,91374,91371,91373,91370,91381,91383,91369,91368,91379,91382,91384,91351,91353,91367,91377,91380,91349,91352,91354,91378,91347,91350,91348,91361,91363,91391,91393,91362,91364,91392,91394,91359,91389,91360,91357,91387,91358,91390,91388,96213,96214,96215,96216,96217,96218,96219,96220))"
          }
        },
        {
          "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": 96,
            "filtered": "100.00",
            "cost_info": {
              "read_cost": "24.00",
              "eval_cost": "9.60",
              "prefix_cost": "53.09",
              "data_read_per_join": "1K"
            },
            "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": 4,
            "filtered": "5.00",
            "cost_info": {
              "read_cost": "24.00",
              "eval_cost": "0.48",
              "prefix_cost": "86.69",
              "data_read_per_join": "12K"
            },
            "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
91347 7217M,7337 0
91348 7217M,7337 0
91349 7337,7217M 0
91350 7337,7217M 0
91351 7217M,7337 0
91352 7217M,7337 0
91353 7337,7217M 0
91354 7337,7217M 0
91357 7337,7217M 0
91358 7337,7217M 0
91359 7337,7217M 0
91360 7337,7217M 0
91361 7217M,7337 0
91362 7217M,7337 0
91363 7217M,7337 0
91364 7217M,7337 0
91367 7217M,7337 0
91368 7217M,7337 0
91369 7217M,7337 0
91370 7217M,7337 0
91371 7217M,7337 0
91372 7337,7217M 0
91373 7337,7217M 0
91374 7337,7217M 0
91377 7337,7217M 0
91378 7337,7217M 0
91379 7337,7217M 0
91380 7217M,7337 0
91381 7217M,7337 0
91382 7337,7217M 0
91383 7337,7217M 0
91384 7337,7217M 0
91387 7337,7217M 0
91388 7337,7217M 0
91389 7337,7217M 0
91390 7337,7217M 0
91391 7337,7217M 0
91392 7217M,7337 0
91393 7217M,7337 0
91394 7217M,7337 0
96213 7217M,7337 0
96214 7217M,7337 0
96215 7337,7217M 0
96216 7217M,7337 0
96217 7217M,7337 0
96218 7337,7217M 0
96219 7337,7217M 0
96220 7217M,7337 0