We have already reported here about the direct opening of PDF files managed on SharePoint Online via a context menu. The good news: We have also developed a solution for local SharePoint environments to make this possible!
The prerequisite is that you have installed SharePoint Designer 2013 on your SharePoint Server. Administrative rights on the SharePoint server and on each client must be available for setup.
Your SharePoint 2016 environment must be prepared accordingly by storing the SharePoint app that we developed, which extends the context menu with the entry for opening the PDF file, as a custom action for each affected document library.
The corresponding program must then be installed on each client.
Now your users can be happy that they can open PDF files directly from SharePoint for editing in the appropriate app with just one click in the context menu:
By the way: Instead of entering the user-defined action (Custom Action) into each document library with the SharePoint Designer, this can be done automatically by a PowerShell script. The prerequisites are the necessary rights in SharePoint and the SharePoint 2016 Management Shell.
We would be happy to advise and support you with the implementation and creation of the scripts!