Treasures Old and New by Jeske, John C.
Why isn't the Book of Concord given in Latin or German? I am genuinely curious.
Because the focus is on the Biblical languages? The preface (which can be read on the Logos preview) says it's designed for pastors who want to maintain their proficiency in the Biblical languages.
The Book of Concord is available in Latin and German. The name is the Concordia Triglotta in English, in German, and in Latin. The Concordia Triglotta in book form includes all three languages. Logos has the Concordia Triglotta divided into three different e-books, so you have to pay for each language individually from what I found.