This site introduces unknown Emanuel Bach (C. P. E. Bach).
ChatGPT4o writes as follows (please note that it may not be accurate):
C.P.E. Bachʼs flute sonatas hold an important place in 18th-century flute music, strongly reflecting the characteristics of the Empfindsamer Stil (sensitive style). These sonatas, while grounded in the Baroque tradition, also anticipate elements of the Classical [and Romantic] periods, developing music that is both free and emotionally rich.
Many of these sonatas are based on binary or ternary forms, typically following a fast-slow-fast movement structure. Notably, they feature delicate, lyrical melodies and harmonic progressions that make full use of the fluteʼs soft and gentle tone. Additionally, bold modulations and improvisatory ornamentations are incorporated, challenging the performerʼs expressive abilities.
These sonatas expand the possibilities of the flute, posing technical and expressive challenges for performers. At the same time, they significantly influenced later instrumental works by composers such as Haydn and Mozart, contributing greatly to the development of flute music.