While the name is pronounced "Mirèio" in Provence (and indeed written that way in the newer pronunciation-based Mistralian norm), the Classic Norm of Occitan (more spelling-consistent, and what the majority of Occitan names on this site are using) spells it "Mirèlha" or "Mirèia", as most -a words are pronounced with a long O sound. See here: https://www.locongres.org/images/flipbook/lexics/prenoms/files/assets/basic-html/index.html#58 This link gives Mirelha as the common form, and Mirèlha/Mirèia in Provence. However, their multidictionary at https://locongres.org/oc/aplicacions/dicodoc-oc/dicodoc-recerca gives Mirèlha for the other two southern dialects as well (only the Limousin and Vivaroalpine dialects spell the è sound without an accent, so it's more likely that Mirèlha is the commonmost orthography.)https://oc.wikipedia.org/wiki/Mir%C3%A8lha The Occitan Wikipedia, which uses the classic norm, also has "Mirèlha" first in the article on Frederic Mistral's work by the same name (again in the Provençal dialect). [noted -ed]
See here: https://www.locongres.org/images/flipbook/lexics/prenoms/files/assets/basic-html/index.html#58
This link gives Mirelha as the common form, and Mirèlha/Mirèia in Provence. However, their multidictionary at https://locongres.org/oc/aplicacions/dicodoc-oc/dicodoc-recerca gives Mirèlha for the other two southern dialects as well (only the Limousin and Vivaroalpine dialects spell the è sound without an accent, so it's more likely that Mirèlha is the commonmost orthography.)
https://oc.wikipedia.org/wiki/Mir%C3%A8lha
The Occitan Wikipedia, which uses the classic norm, also has "Mirèlha" first in the article on Frederic Mistral's work by the same name (again in the Provençal dialect). [noted -ed]