This site introduces unknown Emanuel Bach (C. P. E. Bach).
ChatGPT4o writes as follows (please note that it may not be accurate):
Emanuel Bachʼs Fantasia in D minor Wq. 113-3 (H. 195) is a work that showcases his unique musical style. This piece is characterized by its free form and improvisational elements, featuring bold modulations that surprise the listener throughout. The rhythm is varied and dynamic, alternating between tension and release, which captivates the audience. The emotional range is broad, skillfully weaving introspective sections with dramatic parts. This work, which highlights the richness of expression in Bachʼs music, well represents his innovative spirit.