Export arborescence of folders containing PDF

When exporting (File>Export>Files…) an arborescence of folders (a folder A that contains other folders (a, b, …) with PDF inside), the export results in a folder named A with all the PDF files (correctly renamed) and empty folders (a, b,…). In Scrivener 1 for windows, the export provided a correct arborescence.
For a unique folder with PDF inside, the export works flawlessly.

WIndows 10 - version 20H2 - Scrivener 3 beta 11

There is a (poor) workaround.
Just move child folders in a folder tree that has been manually built.