in confluence with the avoiding situation exposed by Anneza.
I checked in babynamesofireland.com (because there are audio records of the names) and in Irish Muirgheal
is pronounced with a sound [u] (in a way very similar to Muriel
in Catalan or in Spanish), so the adaptation of Muirgheal
through the Latin or even through the French/the Norman
has a lot of sense. And I can see the evolution from [u] to a schwa and then to [e] or [a].
is an old fashioned name in English, I didn't hear it in real life (I think) and I don't know if nowadays in the English of Ireland Muriel
is pronounced with [u] (like in Irish) or with [ju] (like in the general modern English pronunciation). Next Monday
I will ask my English teacher about the pronunciation of Muriel