The Nautch Girl (also known as Qissa Rangeen (Colourful Tale) or Nashtar (The Surgeon’s Knife)) and Umrao Jan Ada (Pic 1 is an extract from this novel) are among early novels in India and both have a dancing girl/courtesan as the heroine.
In the 1790s it was common for cantonment towns like Kanpur (where The Nautch Girl is set) to have dance entertainments for British officers and also their families. Pic 2 is a well known painting of Col Polier at a nautch roughly around the same time as Nashtar’s publication. The dress looks like an ankle grazing anarkali though I can’t say for certain if this was the norm for this decade.
Umrao Jan Ada, though written in 1899, ends its tale around 1857 which suggests that she was a courtesan at her peak in the 1820s-1830s. Almost all paintings of this time have the very flared trousers (pic 3) for Muslim courtesans (also seen in the 1856 set Shatranj ke Khiladi).
Both Khanum Jan of The Nautch Girl and Umrao Jaan are also educated women as was the case for girls in a better class of establishment.
Pic 4 is of course of the two movie versions of Umrao Jaan.