Replace all E by Em

In V2 I was lazy enough to notate all Em as E in a Em score (by the way it wasn't just laziness, that's also one way to notate "Em" on base diatonic accordion without 3rd)
Anyway so is it.
Now with V3 playing the chords, these E won't do.
So the question... what's the easiest way to change them in Em? I have found #47726 but it hasn't been implemented apparently.