My suggestion is the most appropriate translation in my opinion, however there are alternatives:

- 'Regional Prosecutor General' may also be translated as 'Public Prosecutor' or equivalent.

- 'comarca' can also be translated as 'district'

My suggestions follow wording featured on the Portal do Ministério Público:

https://en.ministeriopublico.pt/node/31565
https://en.ministeriopublico.pt/en/pgregs-en

I don’t believe the phrase is in reference to the Attorney-General’s Office. Please note that it reads “Procuradoria”, not “Procuradoria-Geral”!

My research indicates that the “Procuradoria da República” is under the “Ministério Público” (Public Prosecutor’s Office) in both countries (Portugal and Brazil).

“Na sede de cada comarca (assinalada no mapa), existe uma Procuradoria da República da Comarca, órgão a que compete especialmente dirigir, coordenar e fiscalizar a atividade do Ministério Público da comarca e nos departamentos e procuradorias que a integram (artigos 73.º /1 e 74.º EMP).

A Procuradoria da República da Comarca é dirigida por um procurador-geral-adjunto ou procurador da República designado magistrado do Ministério Público Coordenador (artigo 73.º/3 EMP), nomeado, em comissão de serviço, pelo Conselho Superior do Ministério Público (artigo 162.º EMP).“ https://www.ministeriopublico.pt/comarcas

From here, I’m not sure exactly which way to go, but it seems to me that a “procurador da República” is kind of a “federal prosecutor”. In terms of US law, it would be equivalent to the “Assistant United States Attorney”.

“An Assistant United States Attorney (AUSA), or federal prosecutor, is a public official who represents the federal government on behalf of the U.S. Attorney (USA) in criminal prosecutions, and in certain civil cases as either the plaintiff or the defendant. (…) U.S. Attorneys and their offices are part of the Department of Justice.” https://en.wikipedia.org/wiki/United_States_Attorney

As explained earlier, there is a prosecutor’s office in each district, hence the use of the preposition (“at”) to indicate the location.

Plenty of examples with “Portugal’s Prosecutor’s Office”: http://google.com/search?q="Portugal's Prosecutor's Office"

PS: As explained in my answer to another question, “comarca” should be translated as “(judicial) district”.


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Note added at 5 hrs (2021-07-09 14:29:35 GMT)
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Just like the “Procuradoria da República” supervises the activities of the “Ministério Púbico”, “each U.S. Attorney supervises as many as 350 assistant U.S. attorneys, and as many as 350 more support staff.” https://www.capitolmarkets.com/spotlight/spotlight-the-offic...