I found on the Helix Toolkit an example, which is called to ScatterPlot, which is really close what I really need. But I can't find anything about how can I add something onclick event listener to the created objects (in this case to the sphere). This adds the sphere to the 'playground'.
scatterMeshBuilder.AddSphere(Points[i], SphereSize, 4, 4);
The basic goal is to add every sphere an onclick event listener and when the user choose a color and click one of these spheres it will change to the selected color. It's possible to add onclick listener (or something equal with it) to the spheres.
One year later... Maybe someone will find this usefull.
A solution that worked for me revolves around extending the UIElement3D class, this has a bunch of standard events that you can override. e.g MouseEnter,MouseClick etc. Source below.
To add them to the playground
Finally add the container as a child to a ModelVisual3D object.