... as well as with GRUB2 (though IMHO with some added complexity) once you are in the bootmanager you can chainload *everything* or *nearly everything*, whilst ...
Clover supports GRUB2 out-of-the-box.
So it does also kind of semi support its sibling grubfm by a1ive.
You just have to rename grubfmx64.efi to grubx64.efi and copy it to [FOLDER_3] like
and move [FOLDER_3] to "USB_ESP"/ like folder 1 and 2 previously.