flattering signed pdf files

I want to flatten pdf files with electronic signatures. I have found the action from flattering pdf files so that comments and markups become part of the pdf files and cannot be moved around in Acrobat Reader but this action does not work for files with electronic signatures. For these files I use Print to PDF action but this requires clicking for each file to be printed. For large number of files it is time consuming. I am looking for solution to this problem, how to flatten this files or how to modify Print to PDF action so that it will automatically process large number of files without need for clicking on each print.