Features added from the REST endpoint in a projection of Belge_Lambert_1972, well-known ID (WKID):31370, to a hosted feature service published to Portal for ArcGIS with a projection of Web Mercator Auxiliary Sphere, well-known ID (WKID):3857, are displayed at an offset in Map Viewer.
This is no longer reproducible in ArcGIS Enterprise 10.8.1, which is the current minimum supported version of ArcGIS Enterprise. This issue is closed as non-reproducible. Log a new issue if this is still happening in newer versions of ArcGIS Enterprise with detailed steps to reproduce.
解决办法
Publish the data in World Geodetic System 1984 (WGS84) as a hosted feature service with a projection of Belge_Lambert_1972.
Apply the necessary datum transformation to the data in Web Mercator Auxiliary Sphere in the map document (MXD) prior to publishing as a hosted feature service.
Assign a projection of Belge_Lambert_1972 to the data frame, and apply the correct datum transformation, Belge_1972_To_WGS_1984_3.