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 (
    84706, 91053, 88941, 88512, 88141, 88144, 
    88939, 90126, 90129, 84702, 84705, 
    91052, 84697, 84698, 88946, 88947, 
    88948, 88140, 88143, 88508, 87890, 
    88943, 88944, 88945, 84695, 88937, 
    87877, 90124, 90125, 90127, 90128, 
    88515, 88518, 87282, 87290, 88514, 
    88517, 88511, 87876, 88506, 88507, 
    88510, 90828, 90827, 87995, 87882, 
    86861, 87875, 90826, 87881, 87787, 
    87786, 87874, 87792, 87798, 87880, 
    87873, 87785, 87790, 87796, 87789, 
    87795, 87758, 85974, 85975, 85977, 
    85978, 85979, 85980, 85981, 85982, 
    85983, 85984, 85985, 85986, 85987, 
    85988, 85989, 85990, 85991, 85992, 
    85993, 85994, 85995, 85996, 85997, 
    85998, 85999, 86003, 86004, 86005, 
    86006, 86007, 86008, 86009, 86010
  ) 
GROUP BY 
  cscart_products_categories.product_id

Query time 0.00719

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "137.81"
    },
    "grouping_operation": {
      "using_temporary_table": true,
      "using_filesort": true,
      "cost_info": {
        "sort_cost": "11.90"
      },
      "nested_loop": [
        {
          "table": {
            "table_name": "cscart_categories",
            "access_type": "ALL",
            "possible_keys": [
              "PRIMARY",
              "c_status",
              "p_category_id"
            ],
            "rows_examined_per_scan": 208,
            "rows_produced_per_join": 8,
            "filtered": "4.00",
            "cost_info": {
              "read_cost": "20.72",
              "eval_cost": "0.83",
              "prefix_cost": "21.55",
              "data_read_per_join": "21K"
            },
            "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')))"
          }
        },
        {
          "table": {
            "table_name": "cscart_products_categories",
            "access_type": "ref",
            "possible_keys": [
              "PRIMARY",
              "link_type",
              "pt"
            ],
            "key": "PRIMARY",
            "used_key_parts": [
              "category_id"
            ],
            "key_length": "3",
            "ref": [
              "nuie_scalesta_net.cscart_categories.category_id"
            ],
            "rows_examined_per_scan": 117,
            "rows_produced_per_join": 11,
            "filtered": "1.22",
            "cost_info": {
              "read_cost": "2.33",
              "eval_cost": "1.19",
              "prefix_cost": "121.75",
              "data_read_per_join": "190"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "link_type"
            ],
            "attached_condition": "(`nuie_scalesta_net`.`cscart_products_categories`.`product_id` in (84706,91053,88941,88512,88141,88144,88939,90126,90129,84702,84705,91052,84697,84698,88946,88947,88948,88140,88143,88508,87890,88943,88944,88945,84695,88937,87877,90124,90125,90127,90128,88515,88518,87282,87290,88514,88517,88511,87876,88506,88507,88510,90828,90827,87995,87882,86861,87875,90826,87881,87787,87786,87874,87792,87798,87880,87873,87785,87790,87796,87789,87795,87758,85974,85975,85977,85978,85979,85980,85981,85982,85983,85984,85985,85986,85987,85988,85989,85990,85991,85992,85993,85994,85995,85996,85997,85998,85999,86003,86004,86005,86006,86007,86008,86009,86010))"
          }
        },
        {
          "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": 11,
            "filtered": "100.00",
            "cost_info": {
              "read_cost": "2.97",
              "eval_cost": "1.19",
              "prefix_cost": "125.92",
              "data_read_per_join": "190"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "position"
            ]
          }
        }
      ]
    }
  }
}

Result

product_id category_ids position
84695 7208M,7241,7309,7346
84697 7208M,7241,7309,7346
84698 7208M,7241,7309,7346
84702 7208M,7241,7309,7346
84705 7208M,7241,7309,7346
84706 7208M,7241,7309,7346
85974 7148,7207,7224M 0
85975 7148,7207,7224M 0
85977 7148,7207,7224M 0
85978 7148,7207,7224M 0
85979 7148,7207,7224M 0
85980 7148,7207,7224M 0
85981 7148,7207,7224M 0
85982 7148,7207,7224M 0
85983 7148,7207,7224M 0
85984 7148,7207,7224M 0
85985 7148,7207,7224M 0
85986 7148,7207,7224M 0
85987 7148,7207,7224M 0
85988 7148,7207,7224M 0
85989 7148,7207,7224M 0
85990 7148,7207,7224M 0
85991 7148,7207,7224M 0
85992 7148,7207,7224M 0
85993 7148,7207,7224M 0
85994 7148,7207,7224M 0
85995 7148,7207,7224M 0
85996 7148,7207,7224M 0
85997 7148,7207,7224M 0
85998 7148,7207,7224M 0
85999 7148,7207,7224M 0
86003 7148,7207,7224M 0
86004 7148,7207,7224M 0
86005 7148,7207,7224M 0
86006 7148,7207,7224M 0
86007 7148,7207,7224M 0
86008 7148,7207,7224M 0
86009 7148,7207,7224M 0
86010 7148,7207,7224M 0
86861 7148,7207M 0
87282 7148,7207M 0
87290 7148,7207M 0
87758 7148,7207M 0
87785 7148,7207M 0
87786 7148,7207M 0
87787 7148,7207M 0
87789 7148,7207M 0
87790 7148,7207M 0
87792 7148,7207M 0
87795 7148,7207M 0
87796 7148,7207M 0
87798 7148,7207M 0
87873 7208M,7241,7309,7346
87874 7208M,7241,7309,7346
87875 7208M,7241,7309,7346
87876 7208M,7241,7309,7346
87877 7208M,7241,7309,7346
87880 7208M,7241,7309,7346
87881 7208M,7241,7309,7346
87882 7208M,7241,7309,7346
87890 7208M,7241,7309,7346
87995 7148,7207,7208M 0
88140 7208M,7241,7309,7346
88141 7208M,7241,7309,7346
88143 7208M,7241,7309,7346
88144 7208M,7241,7309,7346
88506 7208M,7241,7309,7346
88507 7208M,7241,7309,7346
88508 7208M,7241,7309,7346
88510 7208M,7241,7309,7346
88511 7208M,7241,7309,7346
88512 7208M,7241,7309,7346
88514 7208M,7241,7309,7346
88515 7208M,7241,7309,7346
88517 7208M,7241,7309,7346
88518 7208M,7241,7309,7346
88937 7208M,7241,7309,7346
88939 7208M,7241,7309,7346
88941 7208M,7241,7309,7346
88943 7148,7207,7208M 0
88944 7148,7207,7208M 0
88945 7148,7207,7208M 0
88946 7148,7207,7208M 0
88947 7148,7207,7208M 0
88948 7148,7207,7208M 0
90124 7148,7207M 0
90125 7148,7207M 0
90126 7148,7207M 0
90127 7148,7207M 0
90128 7148,7207M 0
90129 7148,7207M 0
90826 7208M,7241,7309,7346
90827 7208M,7241,7309,7346
90828 7208M,7241,7309,7346
91052 7208M,7241,7309,7346
91053 7208M,7241,7309,7346