ChartType Sankey diagram

We are using the Vaadin component Chart in our application and so far it have been serving us well on standard chart-types like line and bar, but now we need to implement a Sankey diagram in our application. The Sankey diagram is a chart type that is supported by the HighChart.js library.

Is there a reason this ChartType is not implemented in the Vaadin component?
Are there any roadmap regarding whats in development on components so I can check if this is going to be implemented at any point?
How would I go about to implement this my self? Do I need to make a whole new custom component from scratch with the HighChart.js library or is there a way to extend the build in component.

I would really love to be pointed in the right direction regarding how I can make an extended chart class that can handle sankey ChartType. I see in the node_modules on the client side that the library for sankey is imported so I guess it might be possible? A hint if this is even possible or should I start to look for a nother solution would be appriciated.