Total Commander (shareware, no adverts, no restrictions)
All droid devices come with a basic file manager, which you eventually ignore for something else, or compliment with a suite of other file transfer apps.
Total Commander is a mini version of the classic desktop file manager.
If you have ROOT it can be used for more advanced file management.
There are many plugins to add support for a variety of other file storage and transfer methods, including handy bluetooth and wifi device to device transfers, google drive, one drive, drop box and network shares.
http://www.ghisler.com/android.htm
For management from your desktop computer the Total Commander ADB plugin makes it easy to extract or fill your devices, and even install or remove apps including system and pre-installed apps.
This will work with any PC file manager that is compatible with Total Commander plugins.
If your screen is broken or you can’t get into your device, this makes it easy to use the side door.
https://www.uniqtec.eu/applications/android-adb.html
Both of these will help you find all the cruddy temp folders that cleaner apps often miss