Not sure what you mean here. If the asset is loaded but it takes a while to render then there is something else going on.
My guess now without seeing a reproducible is that in the scene that is being loaded, there’s a lot of entities/logic being created/ran on the first frame that’s what’s causing a ‘freeze’ since this is all single threaded.
If this is the case, not much you can do besides adding your own custom loading where entities and logic is ran over several frames/time in chunks
Edit: Now that I read that you put in a delay before the scene load, this is likely to be the cause as it’s creating the new scene before the render call in the current frame is called which means that the icon won’t appear until the scene is loaded and only for a single frame.