Best position title for International/USA context
Job titles have no international context.  They have only a local context.  (They don't even have a national context.  American academics can all easily figure out that Professors at SUNY Adirondack, SUNY Geneseo, and SUNY Stony Brook - all universities in the same state system - are vastly different jobs with vastly different qualifications.)
Just give your official title (in the local language if not English - this emphasizes that it's not translatable).
In the rest of your application materials, you can explain what your job duties are and what qualifications you have, and people will figure it out.