There is no direct way to plot the contact pressure * position in mechanical. I guess, the workaround you are using is good. But instead of exporting contact pressure results for the whole surface, you can export for the required edge(path is not supported). So that you will have results only for the required nodes. Also, use LOCX( or LOCY or LOCZ as per the direction) user-defined result to get the position of nodes on the same edge selected for contact pressure. You can use multi object export ACT to export contact pressure and LOCX results to export them together and then use excel to plot the graph.
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