We can develop custom chart widgets from Highcharts samples.

(Note: OutSystems Platform only offers the license of the Highcharts version it includes)

You can refer to the Highcharts samples in the following document (index.htm). 

https://code.highcharts.com/zips/Highcharts-6.1.4.zip

After that, you can copy and paste the JavaScript source code from the index.html file or Web Browser, and create your own Stream Graph or any other one which-ever you like the most.

Preview Link :- https://personal-vupnklpl.outsystemscloud.com/StreamGraph/WorldMapScreen?_ts=637993623927609313