There are many plotting libraries out there for Python, Javascript, .NET, Qt, ... The only pure C++ OpenCV libraries that I found are
https://github.com/opencv/opencv_contrib/tree/master/modules/plot
Quite disappointing for a contrib module. Very view features. No documentation. No axes.
https://github.com/leonardvandriel/cvplot
Much better. Clean interface and a lot of features. But no way to add custom drawables.