ABBYY FineReader automatically convert files

This was an extremely interesting question and finding a way to do what you described, would be very helpful to me as well. So I had a quick look into the matter and that’s what I came up with, Although I regret to say that the best I can do is push you one small step forward.
First, there is an app for windows that does exactly what you want it to do, so there must be A similar app for Mac as well.
What follows is what they state in their website.
‘The automation feature in PDF Converter app allows for on-the-fly conversion of documents from a watched folder to PDF files in an output folder. It is even possible for the administrator to configure multiple folders for automation, as well as perform additional set of actions, such as, apply watermark, password or page number. Once applied, it is just a matter of you or other co-workers copying or putting documents to one of this configured folder to convert to PDF files automatically, from any workstations. This provides an easy way to streamline the document processing tasks for all users in the organization.’
This is the link if you want it.https://www.assistmyteam.com/pdf-converter-for-windows/pdf-automation/

If you want to get there yourself and are willing to put in the time and energy, you could probably create shortcuts and automation app sequences to accomplish your end goal with only a few or perhaps even only a single keystroke. Creating it is the hard part.

Good luck!