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 = 7156 
WHERE 
  cscart_products_categories.product_id IN (
    87654, 87655, 87668, 87669, 87675, 87676, 
    87682, 87683, 87703, 87704, 87713, 
    87715, 87727, 87729, 88692, 88693, 
    88739, 88740, 92186, 92187, 92188, 
    92189, 92190, 92441, 85642, 85582, 
    86901, 90023, 90039, 90055, 91840, 
    91841, 91842, 91843, 91845, 91846, 
    91847, 87581, 87596, 87611, 88150, 
    88152, 88792, 86891, 87657, 87671, 
    87678, 87685, 87706, 87719, 87733, 
    88696, 88743, 91868, 91849, 91850, 
    91851, 91852, 91853, 91854, 91855, 
    91857, 91858, 91859, 91860, 91861, 
    91862, 91863, 92227, 82402, 88146, 
    88589, 92210, 85577, 92373, 84244, 
    84243, 88585, 92383, 92384, 92385, 
    92386, 92387, 92388, 92389, 84242, 
    88584, 91889, 91890, 91891, 92333, 
    92334, 92335, 92336, 86888, 92365
  ) 
GROUP BY 
  cscart_products_categories.product_id

Query time 0.00323

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "121.78"
    },
    "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": 214,
            "rows_produced_per_join": 214,
            "filtered": "100.00",
            "using_index": true,
            "cost_info": {
              "read_cost": "21.74",
              "eval_cost": "21.40",
              "prefix_cost": "43.14",
              "data_read_per_join": "3K"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "link_type"
            ],
            "attached_condition": "(`nuie_scalesta_net`.`cscart_products_categories`.`product_id` in (87654,87655,87668,87669,87675,87676,87682,87683,87703,87704,87713,87715,87727,87729,88692,88693,88739,88740,92186,92187,92188,92189,92190,92441,85642,85582,86901,90023,90039,90055,91840,91841,91842,91843,91845,91846,91847,87581,87596,87611,88150,88152,88792,86891,87657,87671,87678,87685,87706,87719,87733,88696,88743,91868,91849,91850,91851,91852,91853,91854,91855,91857,91858,91859,91860,91861,91862,91863,92227,82402,88146,88589,92210,85577,92373,84244,84243,88585,92383,92384,92385,92386,92387,92388,92389,84242,88584,91889,91890,91891,92333,92334,92335,92336,86888,92365))"
          }
        },
        {
          "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": 10,
            "filtered": "5.00",
            "cost_info": {
              "read_cost": "53.50",
              "eval_cost": "1.07",
              "prefix_cost": "118.04",
              "data_read_per_join": "27K"
            },
            "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": 10,
            "filtered": "100.00",
            "cost_info": {
              "read_cost": "2.68",
              "eval_cost": "1.07",
              "prefix_cost": "121.78",
              "data_read_per_join": "171"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "position"
            ]
          }
        }
      ]
    }
  }
}