I typically have several EndeavourOS installations on my computers: one for KDE, one for Hyprland, etc. Thus, I want to have different UEFI entries, but they would all have “endeavouros”, with each one overriding the others.

You can change the grub ID later by issuing a proper “grub-install” program from the running system or by booting it with the live ISO and then chrooting it.

Why not specify a different grub ID during the installation?

It’s easy to do so:

• Once you boot the live ISO, before starting the installation, open a terminal (in the current version, the live environment is KDE, so you open Konsole);
• Open the file “/etc/calamares/modules/bootloader.conf” with an editor (e.g., “sudo nano ./etc/calamares/modules/bootloader.conf”; you need sudo but no password in the live environment);
• Look for the line (near the end):
  
  efiBootloaderId: "endeavouros"

  1	efiBootloaderId: "endeavouros"

  
  and change it to a different string (e.g., “eos-kde” when you install KDE, “eos-gnome” when you install GNOME, etc.);
• Save the file and go on with the installation as usual!

Now, each installation will have a separate and different grub id.