I think you need to try it direct in HA to see if this is the behavior there. Does the switch create an entity? If yes go to dev tools and find the entity. When you press a button you can see the state change and if there is a delay.
There is an entity. Its added as a light. I do see the state change fairly quickly.
This works for me between 2 lights, this is only the on/off commands. See how that responds.
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