Once you’ve connected your Epic Games profile, you will only see the Crowns and Kudos from your primary profile (from the platform you first logged on after connecting your Epic Games Account). Rewards from other profiles cannot be merged or transferred.
However, Items (such as Costumes or Patterns) from your secondary profile can be added to your primary profile for you to use on any platform. To do this, you’ll need to contact Support with your details (remember your Support ID!).