So I know it is possible to upload a map service package for a feature class or layer to ArcGIS online and have the domains for the attributes stay in tact. However I was wondering if there is a way to do this without having to go through that process. I am working for a local government office so they typically do not allow map service packages to be uploaded by just anyone and I would need to be granted access in order to do so. If there is no other way to do this please let me know.
Currently, the best way to create a hosted feature service with domains is by publishing the configured feature class to ArcGIS Online with the domains already configured from ArcMap or ArcGIS Pro.
As this seems like something that you would like to see implemented, I recommend up voting the following idea: