I've had good results installing High Sierra and most recently Mojave on a Lenovo E73.
However, I could only get this to work by configuring these specific BIOS settings:
Security -> Secure Boot = Disabled
Startup -> CSM = Enabled
Startup -> Boot Mode = Auto
Startup -> Boot Priority = try UEFI first. If the USB installer doesn't boot successfully, try Legacy first.
The reason for the above settings is that even if you create the Mojave USB installer with UniBeast 9.2.0 in Legacy Boot Mode or in UEFI Boot Mode, the Lenovo E73 will only successfully boot the Mojave USB installer as UEFI, and the computer will only boot Mojave from the hard disk in Legacy mode.
Any attempt to deivate from this, such as booting Mojave USB installer as Legacy, or setting the hard disk to boot as UEFI, would cause a boot failure.
Therefore you must set Boot Mode and Boot Priority as above before installing, to allow both UEFI and Legacy boot modes during the installation process.
From what I've read elsewhere, this could be a problem with Lenovo's UEFI implementation method, although the computer successfully boots Windows 8 in UEFI mode without complaint . .
After installation, you can change Boot Mode and Boot Priority to Legacy only.