FCPX HLG/HDR ISSUE:
I think we all are having the same issue on FCPX, and tried several options. But when you preview the video in the FCPX's Browser looks amazing! really great colors! it is the best color I've seen from a Sony camera, I understand we don't have HDR monitors, but FCPX should give the preview without the monitor activating the option "Show HDR as raw values" and it does it, but only in the its browser but in the timeline the highlights are blown out, or if you apply a HDR tool with different settings it fixes the highlights but the colors are completely different from the browser preview, desaturated, flat and if you try to color balance it, it never looks the same.
I'm looking forward for a solution, on Davinci Resolve looks good, but I really like to edit on Final Cut.