Here's the button:
<?xml version="1.0"?>
<button backcol="none" display="both" textcol="none">
<label>Create Matching Text Files</label>
<icon1>#newcommand</icon1>
<function type="normal">
<instruction>FileType new=.txt newname="norename:{file|noext}" </instruction>
</function>
</button>
See here for how to add it to your toolbar.
If a text file already exists it will still create a new one, with a sequentially increasing number added to the end of the name. You can delete these afterwards if desired.