Unfortunately ArcGIS Runtime does not honor offset on a scene layer in a web scene or expose a property to set the offset for a scene layer, but this is in our backlog to support in an upcoming release.
A couple questions when you get the chance:
1) What type of scene layer are you using (3d object, integrated mesh, point cloud, point...)?
2) How are you creating the SLPK?
3) Can you share the scene service and/or portal item you have created with the offset?
Thanks Rex Hansen for your reply. Can you please help us in knowing that how arcgis online apply the offset to the slpk. Is it some arcgis server side operation or some client side rendering.
we don't have a way to shared the scene layer with you right now, as it's not an online service.