I haven't built a Hackinbox for quite awhile. Probably five years. My main box, specs in sidebar, runs High Sierra fine. But I wanted to move to Mojave recently b/c of compatibility issues on some key software I regularly use. Bought a Radeon Pulse RX580 for Metal support; long story short, unable to get it to work (pink screen). Not wanting to end up completely wasting my time, I tried chris111's HD 3000 patcher for Mojave (on a test external SSD) and it works. Even Hackintool shows "VDA Decoder: Enabled" (or 'working," whatever the nomenclature) for HD 3000.
HOWEVER, in HD 3000, running Photoshop in Mojave was pretty much a joke. Even by reducing GPU rendering load in PS preferences (taking it down to "Basic" from the Default of "Advanced"), HD 3000 simply doesn't have the muscle to run Photoshop (v.21.1.1.2). In addition, getting on my creaky knees, pulling my box out from the wall, unplugging the video cable from my Radeon GPU and fishing for the mobo iGPU video input is, well, unpleasant.
So, although I can confirm the patcher does work as advertised (& kudos/thx to chris111 for his time & effort), for my usage needs Mojave (not to mention Catalina) is out of reach considering my hardware. Hardware which, at this point in time, I am not able to upgrade. So I'm basically maxxed-out at High Sierra. But thx for this thread, the links and informed comments. I appreciate it!