I want field users to be able to visit a site and have the site name calculated in a form from the geofence they are inside. I have this working in Arcade. I also want users to be able to fill out these forms on the web when they are NOT inside a site geofence, and to be able to choose the site name from the dropdown. I know I can accomplish this in Survey 123, but I want to keep everything in Field Maps forms for this application

Here is my expression.
var geofence = FeatureSetByName($map, "Security_Geofences",['Site'])
var site = First(Intersects($feature, geofence))
if (!IsEmpty(site)) {
return site['Site']
} else {
return null
}