Hello there!
What I can offer is an automatic upload with the Google Drive App of a PDF file and getting the DOCX file inside the same folder. All implemented with JavaScript and Google Apps Script.
There two caveats though.
1. The google scripts can only be ran once per 60 minutes. Which means there will be a script running 24 times a day, say exactly on the hour. So if you upload file at 6:59, it will be processed immediately. but if it will be 7:01, you will need to wait for an hour. The possible solution for this is to have 10 different scripts running, but it is not possible to guarantee when exactly they will run, the timing is set by Google within 60 minutes of you planned time.
2. The PDF files have to be a proper text files. If it is pictures or scans of documents, nothing will come out of it.
3. The specifics of PDF documents does not always allow to convert them into nicely formatted text. It maybe jumbled up or mixed up or not recognized at all. The character encoding also plays massive role.
NOTE: no matter what other developers tell you, none of them will be able to completely overcome the above-mentioned caveats. No matter how professional they are and what languages they use.
Let me know if I can be of help.
Cheers,
Denis