Sometimes I use Photoshop for multiple changing images resolution. How to do that? Open the Adobe Bridge. Then on the left menu, choose a directory with pictures that interest us, and then in the lower pane, press Ctlr + A to select all pictures:
In the next step from the top menu, select processing:
If the Photoshop was not running, it will launch by Adobe Bridge. Then the window below appears. You can choose or change the options of interest: