git clone https://github.com/endeavouros-team/EndeavourOS-packages-lists.git
cd EndeavourOS-packages-lists
ls
will list the files
sudo pacman -S --needed - < <de-wm-name to reinstall>
where <de-wm-name to reinstall> is one of the text files from this repo including eos-base-group what will install needed packages would be there on a default install.
example:
sudo pacman -S --needed - < xfce4
sudo pacman -S --needed - < budgie
sudo pacman -S --needed - < cinnamon
sudo pacman -S --needed - < deepin
sudo pacman -S --needed - < gnome
sudo pacman -S --needed - < i3
sudo pacman -S --needed - < lxde
sudo pacman -S --needed - < lxqt
sudo pacman -S --needed - < mate
sudo pacman -S --needed - < openbox
sudo pacman -S --needed - < plasma
sudo pacman -S --needed - < eos-base-group
Note that installing DE packages this way can cause various problems, e.g. running multiple conflicting bluetooth managers etc.
So doing this is at your own risk. If you proceed, you should be experienced enough to be able to fix any potential problems caused by using these instructions.