When announce to someone that you know someone here/close by and it’s not unreasonable ROLL+CHA and on a hit they’re there. On a 10+ they’re favourably disposed.
The GM will ask you how you know them, and after you’ve rolled in which circumstances you parted.
Has anyone else missed having a BW Circles-roll equivalent? Is it completely off the idiom of the game? Is it solved with the asking of questions?
“Do I know anyone here?” ; “I don’t know, do you know anyone here?” ; “As your gaze wanders the interior of The Bucking Stallion you spot someone you know. Who? … and what do you think they are doing here?”
This kind of thing is easily handled by the GM’s Principles and Moves of the game. However, there’s no harm in creating a move to handle it, as long as the move follows the ethos of the PbtA system and keeps the fiction moving forward. Legacy has a move like this that is very good, asking the roller to choose from a list regarding the NPCs significance, personal problems, whether they care about your problem, and whether or not you owe them a debt. I consider a good example for anyone trying to make a similar move.
Urban Shadows has a few moves of this nature.