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 = 7207 
WHERE 
  cscart_products_categories.product_id IN (
    88960, 88962, 85801, 85802, 84700, 88961, 
    85800, 88957, 88958, 88942, 88969, 
    88970, 88973, 88974, 87280, 87288, 
    89442, 89444, 88967, 88968, 88971, 
    88972, 88955, 88956
  ) 
GROUP BY 
  cscart_products_categories.product_id

Query time 0.01224

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "79.49"
    },
    "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": 88,
            "rows_produced_per_join": 88,
            "filtered": "100.00",
            "using_index": true,
            "cost_info": {
              "read_cost": "9.09",
              "eval_cost": "8.80",
              "prefix_cost": "17.89",
              "data_read_per_join": "1K"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "link_type"
            ],
            "attached_condition": "(`nuie_scalesta_net`.`cscart_products_categories`.`product_id` in (88960,88962,85801,85802,84700,88961,85800,88957,88958,88942,88969,88970,88973,88974,87280,87288,89442,89444,88967,88968,88971,88972,88955,88956))"
          }
        },
        {
          "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": 88,
            "filtered": "100.00",
            "cost_info": {
              "read_cost": "22.00",
              "eval_cost": "8.80",
              "prefix_cost": "48.69",
              "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": "22.00",
              "eval_cost": "0.44",
              "prefix_cost": "79.49",
              "data_read_per_join": "11K"
            },
            "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
84700 7241,7346,7309,7208M
85800 7208M,7241,7309,7346
85801 7309,7208M,7241,7346
85802 7309,7208M,7346,7241
87280 7207M,7148 0
87288 7148,7207M 0
88942 7346,7309,7208M,7241
88955 7309,7346,7208M,7241
88956 7346,7208M,7241,7309
88957 7208M,7346,7309,7241
88958 7241,7346,7309,7208M
88960 7309,7241,7208M,7346
88961 7309,7241,7208M,7346
88962 7241,7309,7346,7208M
88967 7208M,7309,7241,7346
88968 7346,7241,7309,7208M
88969 7346,7241,7309,7208M
88970 7241,7309,7208M,7346
88971 7346,7241,7309,7208M
88972 7309,7346,7241,7208M
88973 7309,7346,7208M,7241
88974 7208M,7241,7309,7346
89442 7207M,7148 0
89444 7207M,7148 0