Starting with Windows ADK 10 v1809, WinPE is now a separate install (Addon) to Windows ADK 10. As with previous Windows ADK 10 releases you find the setup files on the Microsoft Hardware Dev Center: http://docs.microsoft.com/en-us/windows-hardware/get-started/adk-install
Here is a PowerShell script that automates the setup of Windows ADK 10 including the WinPE Addon:
http://github.com/DeploymentResearch/DRFiles/blob/master/Scripts/Install-HYDWindowsADK10v1809.ps1

/ Johan