I have added side structure (normal platform with disable grab ledge)
It is inclined and zig zag so I have used custom collision mask and add hitboxes.
It works but in some parts my character can climb it by jumping on it. on that structure cause it is inclined in upward direction
I tried some quadrilateral patches but still my character jump and can stay on the inclined structure.
Did you try “slope max angle” in the platformer settings?
Making slope max angle helps to stop platformer object from climbing platform but still when you jump on the inclined platform platformer object sticks to the platform it cannot move on it but it sticks to it.
And you would like the platformer to slide down? If so, try to turn that into an event, and let us know where you get stuck. 
You could try adding an invisible wall on the slope