You will need an external MIDI Loopback software (on PC, I know there are a couple of freeware available… on Mac, there is the built-in IAC Bus)…
You need to route a MIDI track, with the Auto LFO inserted on it, out to the Loopback.
Then, in Devices>Device Setup>Remote Devices>Track Quick Controls, you need to set the Track Quick Controls input to be the return of the Loopback, with one of the slots set to the MIDI channel of that MIDI Track, and in the “Address” column, the CC# number that you have chosen for the LFO (“Controller Type”).
If you don’t want to spoil your already set-up Track Quick Controls configuration in the Devices menu, you can, instead, create a new Generic Remote Device (with the MIDI Loopback as its input), and, in this case, you need only one slot, set up as I described for the upper section (MIDI channel and Address (CC# number) ). In the corresponding line in the lower section, set it to Device = “Mixer”, Channel/Category = “Selected”, Value/Action = Quick Controls>“Quick Control 1” (or whichever Quick Control Slot you wish to trigger from the LFO)
I just tried it quickly here myself (using a new Generic Remote Device), and it works a treat 
. (Of course, Cubase has to be in Play, for the LFO to do anything )