How much is construct event system limited say as compared to stencyl block system or clickteam fusion
In what way do you mean limited?
If you are a coder, then the SDK will allow you to extend or streamline some functionality, but as far as I'm concerned, the main limiting factor is the ability of the user.
Im saying without coding could i make a game like hollow knight or ghost song made by stencyl or freedom planet by fusion just with the event system
As zenox said it mainly depends on the user. C2 makes a lot of things very easy, for things that aren't easy you can still do it with events in most cases. The SDK is nice and all but it isn't really necessary unless you want to interface with something outside of C2 like some js library that isn't covered by existing plugins. So most don't need to use it, as the event system can handle any logic you can devise.
Develop games in your browser. Powerful, performant & highly capable.
Thank you guys for the answer and quick responses i really appreciate it