Correctly position accidentals when two notes in different voices at the same place each have an accidental
S5 - Suggestion
From Gould's Behind Bars:
MuseScore's current default is the one on the right.
I ran across this exact situation today looking at the 1812 overture.
Here's a picture from the PDF from IMSLP.
Yes, realistically both are common in the real world. It's *possible* to special case this situation but it gets complicated quick if there are other accidentals involved as well - much less clear what the "correct" behavior should be. For instance, in the 1812 example above, what if there were also an accidental on the B? Would it still make sense to separate the chords given it would need to be by a larger amount? It gets very subjective pretty quickly.
Still, a special case for two single-note chords isn't not entirely unreasonable.