Hi @jin ,
Thanks for your follow up. The short answer is that CesiumJS does not have API support for the capability you are inquiring about at this time. This is an area targeted for improvement, so I noted your use case on the main issue tracking ideas for this effort here Tools and processes for assigning and editing IDs and metadata · Issue #801 · CesiumGS/3d-tiles · GitHub
There are workarounds in Cesium for Unreal which are unfortunately generally not low-effort Adding metadata to the OSM dataset - #2 by Kevin_Ring. If you are interested I can research if similar workflows are available in CesiumJS with the heavy lifitng documented (with a cursory look now I do not see any documented).
Thanks and please let us know if you have more questions or thoughts to share on this topic.
Best,
Luke