I would like to figure out this as well.
I know that VisualArq plugin has this feature but since I don’t need any other features in that plugin the price for it is way to much for me. Here is a gif from their website showing the dynamic elevation annotations.
@Japhy I don’t really understandy what is shown on your screenshot. I am complete beginner to GH. The output number doesnt seem to be a simple +Z height