I've been exploring Gaël Liardon's music, thanks to Scheufele-Leidig's uplad yesterday. I've recorded three of his treatments of this chorale. (Is this the chorale the basis for the most preludes, I wonder.)
This is a five part fugue: two voices in the right hand, on a cornet, two in the left on a cromorne, and one in the pedal. I've classified it as Baroque, though the harmonic idiom isn't entirely 17th/18th century.