Actually, the Translator is the Gate’s Sword Teacher

Eunseo is halfway through translating a shouting match between hunters when the subway floor warms beneath her shoes. Everyone else sees a gate accident. She hears inner power moving under the station like water trapped in a pipe. At home, an old calendar gives her the same warning in four kinds of ink. Circled days stretch across sixty years, and each mark matches a gate that opened somewhere in the world. Eunseo speaks five languages, knows foreign hunter rules, and can read the old fighting schools better than the officials who laugh at them. Joining the Blue Pine Sword School gives her protection, but it also puts a target on her back. A rival school wants the manual fragment in her sash...