bool QueryUserIdMapping ( const [FUniqueNetId](API\Runtime\CoreOnline\Online\FUniqueNetId) & UserId, const [FString](API\Runtime\Core\Containers\FString) & DisplayNameOrEmail, const [FOnQueryUserMappingComplete](API\Plugins\OnlineSubsystem\Interfaces\IOnlineUser\FOnQueryUserMappingComplete) & Delegate )