I shared my unofficial Occlusion Probes port here: Occlusion Probes page-2#post-4349689. It does work on 2019.1+ and can work without any SRP customization as it uses standard SRP callbacks now (also works on built-in). Main package doesn’t have any shaders, only Occlusion Probes “feature”. I put another package for HDRP SG SubGraphs but I give no guarantee this does things properly as I’m no rendering engineer
I did face one issue while working with this though, it does bake the Occlusion Probes texture if the lighting values are low (old style). But if I use realistic lighting values (like 100k intensity for directional light), it will result in occlusion probe result being all white. This seems like something that the custom bake can’t handle right atm so it probably should be compensated somehow. @torbjorn , you have any pointers on where to start looking for the solution for this?