It's been a while, but I seem to remember Dreamrunners actually being really simple to take down on any difficulty.
When they teleport away, I'd do that move with the Roasted Marshmallow Fists where you pull back and burst forward, but I'd charge it. Then, when they were about to pop out at me, which is pretty telegraphed, I'd release it and it would just knock them back.
They pretty much never touched me on any difficulty once I started doing that. I think they even get stunned eventually, so you can rally go to town on them. The damage frames are pretty generous too,
And I mostly used the move where you throw the Spinny-Slicey Blades for everything that required Smurf weapons, including Witches. That and the move where Dante himself spins around are probably the best Smurf moves in the game.
I haven't played it over six months though, so some of this might be off. At least I remembered the weapon names.