I must be missing something but why is editing so bad in ArcGIS Online?
Is it only the Web Editor app that has slicing & dicing features with nothing of the sort in any of the builders or experiences?
Handing out Creator licenses just to be able to give a client an option to split and/or merge existing polygons & update attributes seems so VC inspired.
I spend the majority of time in Desktop & Field Maps so this requirement for a simple slice & dice web app has not been a thing until this week.