What I understand from the licensing and documentation first of all you would need standard license (with oauth login to arcgis online) AND to have that featurelayer to be fetched from featureservice as offline featurelayer.
I couldn't create database with desktop and do anything to it because it is not ArcGis Server featureservice originally.
So I believe it is like this:
Oauth with ArcGis online/Portal (get standard license) - Fetch offline layer to local database - Go offline - do edits - repeat until ready - push back edits to featureserver.