In order to find the same sound, it is good to know how the DC2 gets its sound. I fiund this in an online review:
Using all‑analogue audio circuitry, and based around charge‑coupled delay‑line chips, the DC‑2W shares some of the basic concepts of a conventional chorus pedal, in that it utilises modulated delay lines — but it does so in a far more subtle way. The effect is achieved by using dual modulation sections running out‑of‑phase with each other, each having its own internally set depth and rate parameters, along with cross‑feedback networks that connect the sections. Adding feedback in this way adds further complexity to the effect, giving the impression that there are more than two modulation processes at work — so you don’t hear the familiar churning sound inherent in typical chorus effects. To enable all the modulation options to be delivered with precision in a pedal‑sized enclosure, the LFOs and control circuits in the DC‑2W are digital — though I should stress, for those care deeply about this sort of thing, that the audio signal path itself is entirely analogue. In the original DC‑2, which had only a mono input, everything — both the audio signal path and the control circuitry — was analogue. (Source: https://www.soundonsound.com/reviews/boss-dc-2w-dimension-c)
Now, I am not aware whether the H9 has any stereo chorus algorithms that flip the phase, but I think you can get a very similar sound with the Micropitch algorithm, or alternatively setting up a chorus with a very slow rate.
Hope this helps.
