Can you transfer pre-existing characers to mist of pandaria remix

[Degas-wyrmrest-accord]

Yes, they clarified in the Community Council that all races and classes will be able to participate:

Pandamonium clarification

You will create new Remix characters (Timerunners) for this event on whichever realms you choose. So that can be the realm on which you mainly play, and it can be realms where you have some alts, and it can be a realm that’s completely new to you. When you select a Timerunner and hit ‘Enter World’, you’ll enter the Remix world and play there starting at level 10. After the event ends, your Timerunners will be converted into standard characters and you’ll have them available to you in the charac…