Meissner specialized in the study of early Germanic literature, particularly Medieval German and Old Norse literature, and Medieval Scandinavian law. He was the author of numerous works on these subjects. Meissner was a member of many learned societies, including the Royal Nordic Society of Antiquaries, the Norwegian Academy of Science and Letters, the Göttingen Academy of Sciences and Humanities and the Bavarian Academy of Sciences and Humanities. He was Knight 4th Class of the Order of the Red Eagle and a recipient of the Goethe-Medaille für Kunst und Wissenschaft.
