I'm having a problem with a number of polygon-based feature layers which a created simply by uploading their shapefiles in my ArcGIS Developers Dashboard. The result is that when one or more polygons are selected on the map in Pro and I use the tool to export them to a GeoJSON file, the resultant file does not have the coordinates in lat-long format, but in meters corresponding to the projected coord system (which is 'WGS 1984 Web Mercator (auxiliary spere)' for these layers). Hence, the geometry in the geojson file does not appear properly when loaded in Google Earth/Maps or caltopo. While the work-around is to select to convert to WGS 1984 in Pro's JSON tool, the problem is that such an option won't be available to front-end users using the web app (created with Exp Builder).
I was able to recreate this problem by adding the feature layer as the only layer to a simple map in Pro. FYI, I notice this problem does NOT occur when I create a simple polygon layer in ArcGIS Developers Dashboard and provide as a feature layer (as opposed to importation of a shapefile). The properties of such a feature layer in Pro show that only the GCS is defined but not the PCS, which may explain when exportation of selected polys to geojson works fine,
