Thanks @TitiCuisset , happy to help @ZChurney3 !
Have you already looked into lead scoring? If you’re trying to add points and have a snapshot of this information, that’s the best way to go.
Other than the website analytics included in their timeline, I’m not aware of a way to create a timestamp like what you’re looking to do.
Even if you created a custom property for each topic and tried to build a workflow, it would have to have so many if/then and loops that it would be unmanageable, and I still don’t think you’d get the timestamp to function the way you want.
This is the default activity available in the sidebar, it shows the timestamps, but not limited to specific topics like you’re asking:
And this is the default timeline activity:
These are the existing Web analytics history properties you could leverage in lead scoring:
And you could also use the Conversion information properties to further refine the score.
Hope this helps you get started!