Funny, similar issues happen with explanations and translations of Old Irish too. Eg. in his chapter on Early Irish in the Celtic Languages book Stifter (the modern authority on OIr.!) translated (when making a point about pronoun agreement in copular clauses) Críst, didiu, is sí in chathir literally as ‘Christ, then, she (!) is the city’, which is nonsense; the sentence means literally ‘Christ, then, [he] is her, the city’ and the pronoun agreement with in chathir makes perfect sense. There is no explicit subject pronoun since explicit subject pronouns did not exist in OIr., is on its own means ‘he is’ here.

There has been a very nice article written about this in Old and Classical Gaelic by Damian McManus recently, Identification copula clauses linking substantives of different gender in Early and Classical Irish, doi:10.1353/cel.2021.0012.