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 A Minor Wq. 112-05 (H. 166) is a captivating piece within his keyboard music, characterized by a wide range of emotions that draw the listener in. This piece is based on the rhythm of a polonaise, featuring a distinctive rhythmic feel and flowing melody. The tonality of A minor imbues the entire work with deep emotion. In this composition, Bach skillfully combines rapid passages with slower sections, providing the audience with alternating tension and release. The piece includes many ornaments and improvisational elements, presenting a technical challenge for the performer. The richness of expression in his music is palpable through this work.