Hi,
A GeoPackage file exported from a hosted feature layer in ArcGIS Enterprise 11 is missing a required system tables: gpkg_spatial_ref_sys, gpkg_contents, gpkg_geometry_columns, which leads to the exported geopackage cannot be opened in a 3rd party applications.
A GeoPackage exported from a hosted feature layer in ArcGIS Online does contain the required system tables (see the attached screenshot) and can be used in other systems.
I'm also attaching the exported geopackage files.
Thanks,
Matej