John Palmer writes about the 3rd duo:
Opening with a sonata-form movement set in B flat major and marked Allegro sostenuto, the third of the three Duos, WoO 27, is the most unusual. The secondary key area of the first movement is more a wash of figures and scales than a real thematic passage. The "reprise" of this material in the recapitulation is practically new music; the recapitulation is like the exposition only at its very beginning and end. A direction to repeat the development/recapitulation complex is an early Classical-era trait.WoO 27, No.3, 1st M (Bassoon/Clarinet):
WoO 27/3 : Bassoon and Clarinet
WoO 27, No.1, 1st M is here arranged for 2 Clarinets, and sounding quite nice, I think:
Л.В.Бетховен \ Ludwig van Beethoven - Дуэт для двух кларнетов
Recently posted as a Clarinet/Cello duo, this time WoO 27, No. 2, is a Flute/Oboe duo:
WoO 27.2 Barbara Rosnitschek Flöte und Fagott Brenneke
For one more interesting duo arrangement of these "spurious-yet-ubiquitous" duos, click HERE to see a version of WoO 27, No.1 for Euphonium and Flute.