Bulk Rename Utility

I'm trying to find out how to move an underscore to the front of the filename, does anyone know how to do that? So it would be from "example_1.png" to "_example1.png".

Many thanks in advance!

For the example, can use the RegEx(1) with a 'Match' and 'Replace' like...
(.+)(_)(\d+)$
\2\1\3