I haven’t tried this so it’s just theory at this point.
First, take a look at the MIDI Auto LFO module in a MIDI or Instrument track…
Can the plugin parameter you want to control via LFO ‘learn’ a CC? If so, that’s the easiest and most direct way to do it. Quite a few plugins allow you to right click a control then ‘learn’ a fader/knob/etc. from your MIDI controller. If that’s the case, you can simply use the LFO right there in your MIDI or Instrument track. Don’t forget that with ‘MIDI’ type tracks you also get up to 4 MIDI aux sends, so you could use the same LFO to drive more than one track if desired.
If for some reason you want to operate a VST control directly using that MIDI Track LFO insert instead…this is possible if you make a Generic Remote Device. First you’ll need to make sure all your VST/VSTi instances that you wish to automate in the project are loaded…then you can link MIDI controllers directly to VST controls in the plugin (provided it supports them…most modern VST and VSTi plugins do, but some [such as ARIA Player] only support automation via MIDI events).
Use a virtual MIDI port (Mac) (or loopMIDI on a PC) and route output of a MIDI track (with the LFO module activated) into your ‘Generic Remote Device’.
Once you get it sounding as you like, if you want to freeze the automation to an actual VST/i automation lane, then do a pass with ‘write’ activated for the VSTi in the instrument rack. That’ll make an actual VSTi automation lane and record the automation pass.
Once that’s written you could disable the write and, enable the read (for the plugin in the instrument rack), then disable or get rid of your LFO enabled MIDI track, and your project will continue to play back as recorded even if you load up later and don’t have your Generic Remote map(s) in place.
Using a virtual MIDI port, a MIDI track, and a Generic Remote Map, is an interesting way to automate a lot of things in CuBase that don’t have dedicated automation lanes. Examples include things like arming/disarming tracks, launching macros, and possibly even stuff like controlling some parameter of the earlier mentioned autolfo insert with another autolfo track
Here’s an interesting image showing most of the things you can remote control via Generic Remote Device:
Note, most plugins supporting VST automation will also add all of their knobs and stuff to the list of stuff you can link controllers for…
You can ‘stack’ (use more than one) ‘Generic Controller Device maps’ if you want a single controller to do more than one thing at once. If a map ever gets in your way, just set its MIDI input to none and that effectively disables it.
Do be aware that Generic Remote Device maps do NOT save with a project. These remain part of your default DAW setup, so if you project depends heavily upon them for some sort of make-shift automation via MIDI track…you’ll want to make a note of it and export a copy of your remote devices along with your project.