Vibrato - Pitch modulation
Tremolo - Amplitude modulation
It’s pitch modulation I am hearing, so most likely is being generated by the Deco. Wobble control?
According to the photo, your Mimic can do stereo in-out, so it could go last... I wonder, by the time your front-end Mimic-generated stereo signal has been through the chorus, delay and reverb, is there anything left of the effect that it provides? My experience of stereo effects (e.g. an obvious one like ping-pong delay) is that they disappear into the reverb mush as you turn up the reverb mix - the stereo effect disappears. Essentially because most cheaper reverbs sum the input to mono before processing to stereo reverb, even though they mix the dry signal to the outputs in stereo. So as the wet mix control increases, any stereo separation in the input signal is lost.
Maybe the Blackhole maintains stereo spread of an input signal? ‘True stereo’ processing?
Still think it is worth trying them in a different order, if only to see how the sound differs
