This Plugin is derived from the Note Names plugin.
It adds the note names of the chords (not just the top note) in all voices (not just voice 1) of either the entire current score (not just the top staff) or on the selected measures/staves as staff text (above the staff for voice 1 and 3, below for voice 2 and 4) and uses note names according to the locale MuseScore is configured for (instead of just the English note names C, D, E, F, G, A, B).
So the output changes with the setting of Menu -> Edit -> Preferences... -> General -> Language, or, if that is set to 'System', the output depends on the language setting of your PC.
As a further extensions it also names notes with sharps, double sharps and double flats and the notename moves aside a bit, if the note would otherwise collide (in treble clef and voice 1 only).
Available locales: English, German, Dutch, Japanese, Italian, French, Spanish, Portuguese, Russian, Romainan, Danish, Norwegian, Swedish, Polish, Slovak, Czech and Greek.
The double sharp and double flat notes as well as Fb, Cb, E# and B# still need translation into French, Spanish, Portuguese, Russian, Romanian and Greek, help is more than welcome.
If you also want it to show courtesy- and microtonal accidentals, change 'false' to 'true' in the plugin code. Note however, that none of these have yet been translated, and their 'clear text' names can be rather long (e.g. "mirrored-flat-slash").
To use the plugin, you must first install it according to the instructions in the Handbook