Thanks v.much. Creating a GUI custom entry (to rename) with this UUID resulted in 2 Linux boot entries appearing in Clover not 1 with my chosen custom title 'Manjaro KDE': one being the main boot entry for Grub/Manjaro and the other being the Windows Boot Loader EFI, shown also as an Ext4 volume (which if clicked on loads Windows 8 not Grub). There is already a separate Windows 8 boot entry in Clover. I have tried various edits in the GUI custom entry (and also using a second custom 'hide' entry using the Manjaro UUID and also the Win EFI UUID) to exclude the Windows Boot Loader EFI labelled as Linux from Clover without success, all they seem to do is keep the 2nd unwanted boot entry as 'Manjaro KDE' and default the main Grub/Manjaro boot entry back to its original title 'Boot Manjaro EFI booot menu from EFI'. It doesn't actually hide either of them.
My architecture:
NVMe 1: OS X 10.14 (default EFI partition)
NVMe 2: Windows 8.1, Manjaro KDE (one EFI partition)
Fusion Drive: OS X 10.12.6 (two EFI partitions, one of each drive)
My set up featured all of the above minus Linux, which I installed (in parallel to Windows, not manually) without removing any of the other drives. I had to replace the contents of the main default EFI folder on NVMe 1 with a back up (pre-Linux) as it would boot me straight into Grub. I do not have a back up of the Windows 8 EFI folder to replace the existing with as a test. I removed the Manjaro folder from the main Clover EFI folder on NVMe 1 and it doesn't seem to matter where I put it, Manjaro still boots up if I click on Manjaro in Clover. I cannot see a Manjaro EFI folder from Windows Partition Manager, all NVMe 2 is showing is a recovery partition, an EFI partition, Windows partition and Manjaro partition.