Well, it doesn't seem to work. I checked ON the "use author_sort as author" in the AZW3 Output, converted a book from EPUB to AZW3, with no effect.
I tried to look inside the AZW3 with the editor, and here's the header of the OPF file:
<?xml version='1.0' encoding='utf-8'?>
<package xmlns="http://www.idpf.org/2007/opf" unique-identifier="calibre_id" version="2.0">
<metadata xmlns:calibre="http://calibre.kovidgoyal.net/2009/metadata" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns
pf="http://www.idpf.org/2007/opf">
<dc:title>Des milliers de places vides</dc:title>
<dc:creator opf:file-as="Inconnu(e)" opf:role="aut">Alain Wagneur</dc:creator>
It should be 'Wagneur, Alain' and not 'Alain Wagneur', right ? So that option in the AZW3 plugin doesn't seem to function....
...