Pardon the semi-OT but this type of file management catches my interest, in part due to issues I've found with a particular "security" camera's android software which, due to a mis-placed cache, leaves private video on device so... building on 2 previously made suggestions:
- MiXplorer Autotasks are the best (and AFAIK the only) existing way to do something like this with MiXplorer (other than to use MiX or another file manager to merely run scripts or batch files).
- For more complete control without requiring coding knowledge (although such knowledge would help) Tasker would be a good choice, especially if you've already invested in using it. I use Tasker shell commands to do some things like this from home screen shortcuts or based on conditions of the device.
Additionally:
- If you happen to be using SD Maid or another utility with "app cleaning" capabilities, you might be able to add the deletion of that cache. but this would not be worth pursuing unless you already use SD Maid (and Tasker would be better choice if you are choosing between one or the other).
On rooted device it is also technically possible to use Tasker to open an app and then simulate screen taps and swipes which would, in this case, navigate to the folder in question then select all files then delete them as if a user was at the screen. Please don't try this!