The newest script contains something like this. Update the script and install ES-Config and Emulationstation. There should be a menu item under “input Config”.
Instruction:
->close emulation station with <F4>
->type:
cd RetroPie-Setup
sudo git pull
sudo ./retropie_setup.sh
->select source based installation
->select ES-Config,Emulationstation and (C) Generate config file for Emulation Station
->start installation