Hi, I just solved the issue.
In 10.15.4 you have to add igfxonln=1 boot parameter, so your working 10.15.3 EFI folder will work if you add this to Clover or OpenCore.
In 10.15.5 the things get more difficult, but solvable. You have to use this ig platform ID 3E9B0000 instead of 3E9B0007 and make sure you have a proper Framebuffer connectors patch.
Now I'm writing from 10.15.5, don't give up, you can solve it.
Lenovo-Air13-IWL "Lilu" (1.4.4) + "WhateverGreen" (1.4) Upgrade to MacOS Catalina 10.15.5 (19F96) HDMI external display black screen! In macOS catalina 10.15.4, the boot parameter enable igfxonln =...
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