On the 175, pulling the handle cuts fuel, hydraulics, and bleed air. Turning the fire handle discharges a bottle. Turning it the other way discharges the other bottle. It has been reported that in the Sim turning the handle back re-establishes fuel, hydraulics and bleed air, and engine restart is theoretically possible, however it's never really been done in the air before. I don't think it's documented anywhere what really can occur - since once you've established that the engine is on fire you aren't in any scenario going to try to bring it back online afterwards.
Do it for both engines. Yikes. That's a lot of workload.
Do it for both engines. Yikes. That's a lot of workload.