Pick a document target instead. Converting your DOCX to DOCX, ODT, RTF or TXT keeps the text, headings and layout. The XLSX route exists only for the case where the tables are the thing you actually want.
Select them all at once in the upload area. Each DOCX is processed separately and comes back as its own XLSX, with a clear per-file message for any that had no tables to extract.
Are my DOCX files private during table extraction?