I haven't played or read enough PbtA to list a "favourite" move, but I like the Theorize move from Brindlewood Bay:
When the Mavens have an open, freewheeling discussion about the solution to a mystery based on the clues they have uncovered and reach a consensus, roll 2d6 plus the number of Clues found, minus the mystery’s complexity.
On a 10+, it’s the correct solution. The Keeper will provide an opportunity to take down the culprit or otherwise save the day.
On a 7-9, it’s the correct solution, but the Keeper will either add an unwelcome complication to the solution itself, or present a complicated or dangerous opportunity to take down the culprit and save the day.
On a 6-, the solution is incorrect, and the Keeper reacts.
I also like how that game's Day and Night moves tweak the typical "Defy Danger" move.
If you like the FFG Star Wars light/dark side point mechanic, you might also like how Fate handles Fate Points. Here's the gist:
Each PC has a pool of Fate Points (FP). At the start of each session, if their pool is lower than their character's "Refresh" score (typically 3), it resets to that score.
A player can spend an FP to:
A player gains FP by:
If you gain FP in a scene, you don't get to use them until the next scene.
The GM begins each scene with FP equal to the number of PCs (plus any gained from the previous scene), pooled across all the NPCs they control. They gain and spend FP in the same ways, except that they don't need to spend an FP to make a compel.