You may change your Epic account display name by visiting the Personal Info page of epicgames.com. Your Epic display name represents you in all Epic Games' on PC as well Unreal Engine Forum and Answer Hub accounts.
Epic display names can only be changed once every 6 months.
Please be aware that Epic display name changes only effect PC/Mac. To change your Twitch, PSN, or XBox Gamertag please contact Twitch, Sony, or Microsoft for assistance.