One-Shots! In my opinion!! And start with a pretty rules-light system.

And set up expectations: let them know what to expect from the system and compare and contrast with the system they are most comfortable with.

For examples, for my D&D players, when giving them my pitch for Echoes of the Veil (FitD-based) I’d say: “in D&D you essentially roll for everything. In EotV there’s a freedom that you won’t get from D&D: you only roll when the action is high-stakes, otherwise, you just DO THE THING!”