2D Sprite and 3D Model

Cesium ion
1

I would like to be able to interchange 2D sprites and 3D models in Cesium. The dataset is loaded via .czml. In this scenario, the 2D sprites are defined under the billboard property. Should the 3D model be defined under the model property? And could these two be interchanged after uploading the file into Cesium?

2

Duplicate; please see: 2D Sprite and 3D Models