Now what exactly is the question? Cubase even has a 31 band GEQ
Stick it into your control room out - if it helps your mixes, it works, if not, it doesn´t work - that simple.
It´s nothing different from using an outboard EQ. Apart from maybe the EQ-sound characteristics itself, which can even be varied in the Cubase GEQ
But in general, you have a point there…