Your Pokemon will probably be hurting; go to the Pokemon Center and heal them. There's a few loose ends to tie up before continue onto Driftveil City. First of all, Pokemon Musicals are now available for you to participate in. These take place at the Pokemon Theater in the north-eastern part of Nimbasa City.
Once you enter, you'll have a Prop Case thrust upon your person. Take it and allow yourself to be walked through a tutorial on how to participate in Musicals. So much pinkkkkk! Bedazzle and bling up a Pokemon of your choice.
Confirm that this is what you want your Pokemon to look like then the man will applaud your amazing talent. That's it! Normally, Pokemon would participate in the Musical itself after dressing up, but that's not forced upon you at least. Once you're done here, feel free to leave.
The only other thing to do is attempt to head to Route 5 . When you do, you'll come upon your rival, Hugh, facing off with four Team Plasma Grunts. Walk over to Hugh and you'll start listening into the conversation. The grunts will surround Hugh and he'll ask for your help.
Talk to either of the bottom two grunts to initiate a battle with them. Once you initiate a battle with one, you must battle the other without a break, so make sure you're ready. Don't worry, you just owned Elesa; you shouldn't have any trouble.
Trainer Battle: Team Plasma Grunt (Top)
Trainer Battle: Team Plasma Grunt (Bottom)
Once they're both beaten they'll retreat. Hugh will provide you with an obligatory thank you (as if he really cares about us!) and will then leave. You might want to heal your Pokemon once more. Once you're ready, it's time to head into Route 5 again!