Thus my asking if you had actually tried to test this from the buss out to a speaker. That would have had the graphic active.
Having struggeled with a DM 2000 doing just this, this past weekend, I can confirm that inserting graphics on mix buses that are in turn just feeding the LR internally in the mixer, does nothing to the audio, even if you're seeing it happen on the screen.
For my situation it was a pain because I wanted to EQ the mix buses with graphics.
But if I was using the buses to mix AND simulatneously feeding the stems to emote speakers, orsimialr, as well, it would have been cool to have a separate "system" EQ for each bus output!