In Photoshop is easy, making an Action (sort of macro) and then applying it in file menu/automate/batch. In Elements, you cannot make actions, you can use actions which are premade and given free or sold, done by full Photoshop users.
There is an super cheap (12$) addon that you can get, which adds batch funcionalities to Elements 9. You can there use it to open multiple files and even do operations to it, etc. I haven't checked if one of the many scripts of the pack does actually that, but you could look there:
The main page is: