I dont think changing her name helped to make it sound more russian since she has "given names" as her name and surname, something like Tom Bob or Jim Kevin and i havent met anyone from Russia with names like that. There was a women's family name Anastasyeva or Anastasieva that belonged to some nobles, so maybe that's what the author meant. Just my two cents here. (Also Anna and Anya is the same name in russian, the first one just being more formal).