Really need to know more about your overall setup and device configuration.
Efficient could be defined as the "fewest number of steps in the process" or "some quantifiable value regarding the transfer speed" of the file(s) during the move.
Safe, in my mind, is simply being sure that the moved data remains intact and is not corrupted during the move. And that I can readily verify that the move was successful. The file remaining readable and functional.
Move has the context of physically transferring the file from one location to another without some duplicate being made.
I use "Copy" which means that a copy of the file is made and placed in the new location (i.e., Onedrive) while the original file remains at the source location...