[Q] Find and move files via 'updater-script'

Hello fellow XDA members!

I am experimenting with a very interesting idea I came up with and I desperately need a way to find all files starting with "xxx" and move them.
I read through all BusyBox documentation sources and found nothing of great help.
If this can only be done in bash (*.sh scripts), could somebody write a code sample as well?
Lastly, do I need to take care of any special problems when I am moving cross-partition (from /system to /sdcard, etc.)?

Thanks in advance and best regards