This plugin is for MuseScore 3 and is intended to allow microtonal/xenharmonic composition with all the accidentals MuseScore supports. Since there is already good support for the graphical accidentals, this plugin only affects playback. The way it works is you create a file representing how you want the naturals (notes A-G) to be tuned, and by what amount each accidental should modify a pitch. Then just run the plugin and a tuning adjustment will be added to each note so it actually sounds in your tuning. See the example files to understand the format and what is possible.