Find and Replace is usually used to replace a value in a field with another value, but what about if you dont have an existing value for the field ?
We can add a value for an empty field as follows
Set Match As to Match Regular Expression and set Find to ^$ (which denotes empty string in regex) it will then replace empty strings with the Replace value but will not modify fields with an existing value
So we have set Select metadata fields to modify to Genre and Grouping . For this set of files they already have a value for Genre but not Grouping , so we only want Grouping to be modified
And we can see by looking at the results that is what has happened.