Output from the node editor to the sequence editor I want to remove a green screen from a video. I know how to do it with the node editor but i can't send the result to the sequence editor. When i try with Add > Scene, it only show me the 3d scene(the default with a cube).
In the VSE preview window press the N key to show the Properties Panel. Look for Scene Preview Render. Turn off Open GL Preview.

This should allow the compositor output to pass to the VSE.

If you had pressed the render button (F12), you would have seen the correct view.

EDIT:
Change the scene strip property > blend type to Alpha Over or Over Drop.