I wish to add a movie clip into Blender then simultaneously use both VSE and Compositor (nodes) to produce various video effects. The VSE offers some nice options, and so does the Compositor. So far, within a single Blender project, I have not been able to figure out how to either -take the output of the VSE movie strip and then run that output through the Compositor for further processing or -take the output from the Compositor movie clip and run that output through the VSE for further processing. I wish to do this all within one project file. Is that possible? Thanks for any ideas.
You can make a separate Compositor Scene that only outputs the compositor result. Then in the VSE scene you can add the Compositor scene as a scene strip.
You can not send the output of the VSE anywhere except for mixdown to codec. Don't worry, everyone asks this at some point.
The VSE is designed to be the end of the production chain.