Log in to your Epic Games account at the Epic website.
Go to Account Settings → General.
Find Display Name and click the Edit icon.
Enter your new name and click Continue.
Note:
You can change it only once every 2 weeks.
Your email must be verified before changing.
Your in-game name is usually your console gamertag:
To change it, update your PSN ID (PlayStation) or Xbox Gamertag through your console’s platform settings.
On Xbox, first name change is free, but subsequent changes cost a fee.