If you're going to announce your presence, you need to learn the language. otherwise, the Borg are just gonna rock up and say, "adrhgafb rgaergv gaaiergqerg" which will leave the people they are attacking going WTF. If the Borg are going to communicate, then they are going to have to use a method they can actually communicate in.
And even if they do use translators, then "Borg" would be whatever the Borg's name for themselves translates into.
And even if they do use translators, then "Borg" would be whatever the Borg's name for themselves translates into.