This was from back when Jhin was being released, with corresponding teasers like this and this, so it predates Arcane by a lot despite fitting in pretty well there.
If you liked this, the artist also released an earlier version of this piece (which I actually slightly prefer the vibe of!) as well as three other pieces: Garen / Lux, Lee Sin / Sona, and Shen / Zed: https://imalsoabignerd.tumblr.com/post/136781112249