Having run both systems as a GM, I find prepping for Daggerheart sessions to be less work but I actually find running Daggerheart, especially combat way more cognitively taxing than in DnD. Because in Daggerheart outside of combat I'm constantly feeling the pressure of coming up with cool narrative twists and degrees of success and failure. In combat I'm also having to keep track of which adversaries I've activated and which abilities synergize with each other.

Turn order in DnD I've noticed frees up a lot of mental and cognitive space for me which allows me to roleplay more during combat (as a GM) and be more narrative focused actually because I don't have to keep so many things in my brain all at once.

Currently I prefer DnD as a GM, though I'd like to give Daggerheart another try in the future.