Currently, AnyChart is a Custom Widget, so it can’t be used inside Pluggable Widgets like the Gallery.
(Compare Pluggable and Custom Widgets – Mx8 | Mendix Documentation)
The other Chart Widgets are all Pluggable Widgets already and they also use Plotly.js (through react-plotly.js), so part of the work is already done.
I will try to do this myself, but since i am not familiar with react or the Pluggable API yet, i will take a long time to do it.
It would be nice if someone familiar with the Chart Widgets, such as the Widget developers/maintainers, did it.