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 = 7148 
WHERE 
  cscart_products_categories.product_id IN (
    88740, 91897, 91898, 91899, 92341, 92343, 
    92344, 85643, 88925, 88926, 88927, 
    91470, 92186, 92187, 92188, 92189, 
    92190, 92441, 82561, 85642, 86249, 
    88070, 88394, 82369, 85582, 86901, 
    90023, 90039, 90055, 90328, 90332, 
    90335, 90336, 90343, 90344, 92488, 
    91840, 91841, 91842, 91843, 91845, 
    91846, 91847, 82375, 87581, 87596, 
    87611, 88150
  ) 
GROUP BY 
  cscart_products_categories.product_id

Query time 0.00082

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "63.86"
    },
    "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": 112,
            "rows_produced_per_join": 112,
            "filtered": "100.00",
            "using_index": true,
            "cost_info": {
              "read_cost": "11.50",
              "eval_cost": "11.20",
              "prefix_cost": "22.70",
              "data_read_per_join": "1K"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "link_type"
            ],
            "attached_condition": "(`nuie_scalesta_net`.`cscart_products_categories`.`product_id` in (88740,91897,91898,91899,92341,92343,92344,85643,88925,88926,88927,91470,92186,92187,92188,92189,92190,92441,82561,85642,86249,88070,88394,82369,85582,86901,90023,90039,90055,90328,90332,90335,90336,90343,90344,92488,91840,91841,91842,91843,91845,91846,91847,82375,87581,87596,87611,88150))"
          }
        },
        {
          "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": "28.00",
              "eval_cost": "0.56",
              "prefix_cost": "61.90",
              "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": "1.40",
              "eval_cost": "0.56",
              "prefix_cost": "63.86",
              "data_read_per_join": "89"
            },
            "used_columns": [
              "product_id",
              "category_id",
              "position"
            ]
          }
        }
      ]
    }
  }
}

Result

product_id category_ids position
82369 7303,7161M
82375 7301,7151M
82561 7183,7283,7167M
85582 7341,7342,7343,7157M
85642 7148,7156,7157M 0
85643 7148,7158M 0
86249 7148,7163,7164M 0
86901 7148,7156,7157M 0
87581 7194M
87596 7194M
87611 7194M
88070 7263M
88150 7194M
88394 7263M
88740 7194M
88925 7226,7225M
88926 7226,7225M
88927 7226,7225M
90023 7194M
90039 7194M
90055 7194M
90328 7265,7247M
90332 7265,7247M
90335 7265,7247M
90336 7265,7247M
90343 7265,7247M
90344 7265,7247M
91470 7226,7225M
91840 7156,7157,7148M 0
91841 7156,7157,7148M 0
91842 7156,7157,7148M 0
91843 7156,7157,7148M 0
91845 7156,7157,7148M 0
91846 7156,7157,7148M 0
91847 7156,7157,7148M 0
91897 7226,7225M
91898 7226,7225M
91899 7226,7225M
92186 7341,7342,7343,7157M
92187 7341,7342,7343,7157M
92188 7341,7342,7343,7157M
92189 7341,7342,7343,7157M
92190 7341,7342,7343,7157M
92341 7226,7225M
92343 7226,7225M
92344 7226,7225M
92441 7341,7342,7343,7157M
92488 7313,7338,7219M