In Cubase we can simply activate the sidechain button on a VST3 plugin, then we can use the effect send of any channel to trigger the sidechain activated effect.
Using VST2, we'd have to either have a specialised plugin, or use quadro busses for example, and after an eon of setting up quadro busses for this purpose - i'm glad to just have a single button to click with the VST3 method.