(Beginner) MIDI Editor Plugins

VST plugins primarily are audio chain manipulation plugins. Is it possible at all to write plugins that can manipulate MIDI events within Cubase in particular? For example, let’s say I wanted to create a plugin that would allow me to enter/edit notes in a different manner from piano roll or score - can this be done with a VST plugin?

Indeed can this be done with some sort of scripting? I’ll be honest, I have “tracker” program that I’ve developed and I’d like to have a go at integrating this editor into Cubase somehow.

Any help or suggestions on how to do this would be greatly appreciated.

There are already two threads that might be interesting for you: