TLDR; There is not a single way to get the state of devices in the scene via scripting, not in Jinja2, not in a Python script.
I am currently using automations to randomly turn on some lights in my house, but I wanted to make this more subtle, I created an automation to turn a device on, then wait a small time, then turn on the other light. This repeats until all lights with a specific label are turned on. Only most lights are plugs, not directly lights.
The problem:
This approach is nice, but this does not work at all for lights where I want to set a specific brightness.
My other approach is to use scenes, this is the most logical way. However, there is no way to set apply the scene for each device with a time in between. So I started scripting, only to find out there is not a single way to get the scenes and the data contained. You can only get which devices are in a scene, but not the exact brightness, state or color from a device in a scene. I wanted to use this data to recreate the scene.apply function so I can turn on devices with a delay in between.
It’s so weird that we can get a lot of data, but not the state of devices in a scene.
At this point scenes just seem kinda weird and are not that useful, since we do have to do a lot of work manually anyway for a lot of things.