How is it different from plotnine? https://projectcodeed.blogspot.com/2020/07/ggplot-grammar-of...
I can think of 3-4 off the top of my head.
Would be curious to hear which ones you're thinking of (since I wouldn't be surprised if the are others, but also am guessing no others hit both points)
Plotnine is the only one another human has told me about, though.
My (wildly speculative) guess for the motivations behind this library would be that Kotlin, as a base, is usable in the other JetBrains IDE's, e.g. reusing the same library and grammar when developing in Java or Ruby.