Visualizing 1-many relationship at single point in ArcGIS online

Question

I need to visualize overlapping activities at the same center point. We have data which was collected at the city level but we need to view individual activities without using layers and filtering in ArcGIS online

Goal -Each activity type to be visualized as unique points 1 activity point or icon per city boundary

• Points are offset from the city spatial point by perhaps 15-20 pixels but within the city boundaries or alternatively anywhere within the city boundary
• The user can can click on the icon and it will bring up a popup window of 1-N records about that activity within the popup window or sidebar. The user can scroll through those records in either the sidebar or popup window.

It is basically doing a 1 - many visualization in ArcGIS online but without doing the layer approach or filtering.

Issues:

• Our original plan was to collect actual activity locations and map it out for every activity. But the theme is related to sustainable energy and some projects are not suitable to be mapped at every point. For example transmission lines, capacity building so our data collection took place at the city level.

I have been trying to find a function in ArcGIS online which can visualize this or accommodate this type of visualization. But there must be a way to do it.