I have a set of stacked maps that I was hoping I can use a swipe function for on a Dashboard. Does anyone know if this is a possible function to do on a Dashboard?
Not in Dashboards, unfortunately. The only place you can use Swipe is Web App Builder or one of the configurable apps like Compare.
As a workaround, I would suggest creating a web app with the Swipe widget in ArcGIS Web AppBuilder and embed that app into your dashboard.
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