Ok, let’s ignore the electromechanical interface at first.
What mostly colors the sound in the illuminist garden is the “shimmer”-like delay/reverberation that can be heard.
The cheapest option to get that effect is afaik the line6 verbzilla:
but there are other options like the line6 M5, or even go the full range with a strymon bluesky/bigsky, eventide space etc… etc…
There might be ways to simulate some of those “shimmer” aspects with the A4 alone but it will never behave and sound the same. Shimmer basically is delay/reverb with pitch shifting, mostly an octave-up in the feedback path. That means the signal in the feedbackloop gets transposed over and over again with each repeat, the output is that ethereal star-dust you can hear.
You can’t do that with the A4’s FX but try to max out reverb settings (making the dry to wet ratio as wet as possible) and feed it with high pitched swells or short impulses. That should help to get at least some of the characteristics of the original.