This site introduces unknown Emanuel Bach (C. P. E. Bach).
ChatGPT4o writes as follows (please note that it may not be accurate):
Emanuel Bachʼs "Alla Polacca in E-flat Major Wq. 114-06 (H. 233)" is a work that stands out for its wide range of emotions within his keyboard music. While based on the rhythm of a polonaise, the piece showcases his unique expressiveness. From the outset, it exudes a bright and festive atmosphere that captivates the listener. The middle section reveals a more introspective and delicate expression, skillfully depicting the shifts in emotion. This work reflects Bachʼs musical curiosity and demonstrates his timeless innovation. Performers are required to have technical proficiency as well as the sensitivity to capture the nuances of emotion.