FYI, I just got a Presonus Faderport version 2 (the 2018 model), which is recognized and integrated out of the box by Mixbus, and there's scrubbing implemented on this control surface by using the "<<" and ">>" buttons when in scroll mode. Holding them down speeds up scrubbing and with a little practice you can scrub backwards and forwards efficiently. However I haven't yet found a way to scrub very slowly using the control surface; I can only scrub at real-time speed or faster.
Overall, I find this one-fader Faderport to be a much more useful tool than I expected, and it works well with Mixbus; it's available as one of the control surfaces in Preferences.
Overall, I find this one-fader Faderport to be a much more useful tool than I expected, and it works well with Mixbus; it's available as one of the control surfaces in Preferences.