Yes, there is a formal night. Cobh itself is a pretty little town and worth an hour or so to wander around when you get back from Cork. It is very easy to do by yourself. Cork town is about 10 minutes walk from the station and at Cobh the station is right next to the ship. The train trip takes 20 mins , takes 20 mins ,
14 euros return, and buy a return ticket from the booking office on the platform.
Yes, there will be a formal night. The ship berths in the centre of town at Cobh. If you want to go into Cork you can get the train, the station is next to the ship.