considering both Fritz and Ryn both identify to female pronouns and that the game identifies you with female pronouns when you are a shemale elf I would consider it the usual pronoun used by Shemale Elves
That's more a problem with the English language really. English never even considered the need to address people as anything other than man or woman, so there's no real way to capture the nature of half-sex short of inventing another bloody new pronoun (which, if past attempts are anything to go by, will never catch on because it's spelled something ridiculous and is unpronounceable by the human tongue).
Sometimes I wish we'd do it as the Koreans do and get rid of gendered pronouns. or do as the Japanese and avoid using third person pronouns altogether. Could be better, could be worse; at least It's not French. One can only assume the writers and by extension citizens of Balhar, who speak a language similar to English, assigned these pronouns based on appearance, which is no less arbitrary a criterion than genitalia. You are, however, correct in that if the game decided to refer to Etheryn as she, the players should do so as well, for consistency's sake, if nothing else. Insisting to do the opposite simply because for some reason a word can determine whether someone turns you on is just petty, really.
It's hardly a priority, but it would be a nice bit of world building to read about how the boreal elves themselves handle this issue. Surely their language would have a more elegant solution.
As a side note, the PC can only be a wyld elf, not quite the same thing. Let's not start melding our elves together as well.