This is the same as the Conversion API in the ChartView (2D).
https://docs.telerik.com/devtools/wpf/controls/radchartview/features/conversion

The API should allow you to provide 2D coordinates on the screen and return the associated coordinates on the chart axes.

Implement Crosshair to show the mouse location(X,Y,Z Axis), depending on that where it is on the plot area.

Create a 3D range bar series. Something like the RangeBarSeries in the 2D chart.

To work this around use DisptacherTimer instead of Task.Run.

This can be integrated in the Chart3DCameraBehavior. The user should be able to pan around the viewport. And also to zoom based on the mouse position. Currently, the zooming is based on the center of the viewport.

Add 3d chartview IsInverse axis options.

Allow stacking of series one over another.

Check the attached project for a possible approach for working this around.