Stacking Density Plot

I was doing some of the TidyTuesday datasets and there is one that looks at Art in the Tates Collection:

The readme has a link to some visualizations here:

How would I go about creating the first graph that contains two density plots on top of each other? In addition, when the “Date Created” and “Date Acquired” are set as date values, you can’t use a density plot. Is there a way to do this in Exploratory?