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 = 7170 
WHERE 
  cscart_products_categories.product_id IN (
    86688, 86690, 83041, 83043, 90877, 90879, 
    90956, 90958, 91070, 91071, 91073, 
    91074, 91075, 89815, 89867, 89939, 
    91505, 82841, 82914, 82987, 85303, 
    85400, 85451, 85502, 86492, 86494, 
    86768, 86770, 84663, 84664, 85306, 
    85308, 85403, 85405, 85454, 85456, 
    85505, 85507, 91114, 91116, 91120, 
    91122, 91125, 91127, 91129, 91200, 
    91202, 91206, 91208, 91211, 91213, 
    91215, 91255, 91257, 91261, 91263, 
    91266, 91268, 91270, 85352, 85354, 
    85349, 91145, 91147, 91151, 91153, 
    91156, 91158, 91160, 82811, 82813, 
    82884, 82886, 82957, 82959, 83331, 
    83333, 83341, 83343, 89493, 89494, 
    89501, 89502, 89509, 89510, 89517, 
    89518, 84302, 84303, 90567, 90573, 
    90579, 82592, 82594, 83355, 83357
  ) 
GROUP BY 
  cscart_products_categories.product_id

Query time 0.00152

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "100.20"
    },
    "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": 176,
            "rows_produced_per_join": 176,
            "filtered": "100.00",
            "using_index": true,
            "cost_info": {
              "read_cost": "17.92",
              "eval_cost": "17.60",
              "prefix_cost": "35.52",
              "data_read_per_join": "2K"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "link_type"
            ],
            "attached_condition": "(`nuie_scalesta_net`.`cscart_products_categories`.`product_id` in (86688,86690,83041,83043,90877,90879,90956,90958,91070,91071,91073,91074,91075,89815,89867,89939,91505,82841,82914,82987,85303,85400,85451,85502,86492,86494,86768,86770,84663,84664,85306,85308,85403,85405,85454,85456,85505,85507,91114,91116,91120,91122,91125,91127,91129,91200,91202,91206,91208,91211,91213,91215,91255,91257,91261,91263,91266,91268,91270,85352,85354,85349,91145,91147,91151,91153,91156,91158,91160,82811,82813,82884,82886,82957,82959,83331,83333,83341,83343,89493,89494,89501,89502,89509,89510,89517,89518,84302,84303,90567,90573,90579,82592,82594,83355,83357))"
          }
        },
        {
          "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": 8,
            "filtered": "5.00",
            "cost_info": {
              "read_cost": "44.00",
              "eval_cost": "0.88",
              "prefix_cost": "97.12",
              "data_read_per_join": "22K"
            },
            "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": 8,
            "filtered": "100.00",
            "cost_info": {
              "read_cost": "2.20",
              "eval_cost": "0.88",
              "prefix_cost": "100.20",
              "data_read_per_join": "140"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "position"
            ]
          }
        }
      ]
    }
  }
}