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 = 7168 
WHERE 
  cscart_products_categories.product_id IN (
    87367, 87366, 87365, 87354, 87364, 82550, 
    87352, 87353, 87358, 87378, 82548, 
    87380, 87357, 87376, 87377, 87374, 
    87379, 82509, 87373, 82508, 82531, 
    87369, 82541, 82440, 87368, 87363, 
    82539, 82530, 82439, 87362, 87361, 
    87356, 82540, 82444, 87360, 82537, 
    87355, 87419, 82523, 82538, 82525, 
    87417, 82438, 87418, 82522, 82547, 
    82443, 91482, 82437, 87416, 82532, 
    82545, 87415, 82524, 87414, 89565, 
    82517, 82546, 89571, 87413, 91476, 
    82516, 82544, 89559, 89569, 87412, 
    82515, 87359, 91475, 82514, 82511, 
    89564, 82485, 82510, 89555, 82499, 
    91473, 82436, 87381, 85611, 82497, 
    91472, 82495, 91471, 82498, 89547, 
    89533, 82493, 82435, 87375, 85606, 
    82496, 85610, 89539, 85605, 82494
  ) 
GROUP BY 
  cscart_products_categories.product_id

Query time 0.00251

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "61.59"
    },
    "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": 108,
            "rows_produced_per_join": 108,
            "filtered": "100.00",
            "using_index": true,
            "cost_info": {
              "read_cost": "11.10",
              "eval_cost": "10.80",
              "prefix_cost": "21.90",
              "data_read_per_join": "1K"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "link_type"
            ],
            "attached_condition": "(`nuie_scalesta_net`.`cscart_products_categories`.`product_id` in (87367,87366,87365,87354,87364,82550,87352,87353,87358,87378,82548,87380,87357,87376,87377,87374,87379,82509,87373,82508,82531,87369,82541,82440,87368,87363,82539,82530,82439,87362,87361,87356,82540,82444,87360,82537,87355,87419,82523,82538,82525,87417,82438,87418,82522,82547,82443,91482,82437,87416,82532,82545,87415,82524,87414,89565,82517,82546,89571,87413,91476,82516,82544,89559,89569,87412,82515,87359,91475,82514,82511,89564,82485,82510,89555,82499,91473,82436,87381,85611,82497,91472,82495,91471,82498,89547,89533,82493,82435,87375,85606,82496,85610,89539,85605,82494))"
          }
        },
        {
          "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": 5,
            "filtered": "5.00",
            "cost_info": {
              "read_cost": "27.00",
              "eval_cost": "0.54",
              "prefix_cost": "59.70",
              "data_read_per_join": "14K"
            },
            "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": "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": 5,
            "filtered": "100.00",
            "cost_info": {
              "read_cost": "1.35",
              "eval_cost": "0.54",
              "prefix_cost": "61.59",
              "data_read_per_join": "86"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "position"
            ]
          }
        }
      ]
    }
  }
}