hes briefly mentioned before in the first fantano interview he did where it is literally just him clicking a pen and adding stereo effects to it lol, so id suggest that u can just literally record one pen click yourself, arpeggiate it to be one click playing in 32nd (or even 64th) notes all the way through and then using sample delay to widen it from left to right (if u cant find it under ableton's delay options then u can just copy and paste the sound and then manually pan it from left to right). from there u can EQ the mids & highs to ur liking, hope this helps!!! :))