It's still advisable to set those BIOS parameters, per STEP 3 of the standard guide.
Thank you for your suggestion. It worked, and I managed to install Movaje, ran multibeast and took the usb stick off before rebooting.
In multibeast I picked the exact same settings as the Macman build which are :
Quick Start > UEFI Boot Mode
Drivers > Audio > AppleALC
Drivers > Disk > Intel Generic AHCI SATA
Drivers > Misc > FakeSMC
Drivers > Network > Intel > IntelMausiEthernet v2.4.0
Drivers > USB > Remove XHCI USB port Limit
Bootloaders > Clover UEFI Boot Mode + Emulated NVRAM
Customer > Graphics > Core Graphics Fixup AKA Whatevergreen
Customer > Graphics > Intel HD630 (Coffee Lake)
Customer > System Definitions > iMac > iMac18,1
I restarted the system and, after the restart, clover launched and I choose to boot from my fresh installed mojave. The apple logo appears, then the progress bar. But the progress bar stops at around 80%.
If I am booting from the usb stick it boots with no problem, but as soon as I am trying to stras without the usb in I am stuck.
Any ideas on what could be the issue ?
Attached the verbose screenshot