I am using exact same model. Here my setting.

For normal
Viewing Mode - Normal
Backlight - 65
Contrast - 85
Brightness - 0
Colour - 51
Tint - 0
Sharpness - 50
Colour Temperature - Normal
Vivid Colour - On
Adaptive Backlight Control - Mid
Intelligent Frame Creation - Min

For HDR - additional setting
Viewing Mode - Custom
Backlight - 85
Contrast - 95
Advanced Settings - HDR Brightness Enhancer - On
Advanced Settings - Contrast Control - Custom
Advanced Settings - Contrast Control Setting 11, 12, 13

I have a 49FX600 tv and I find that screen is too bright and the white is like washout. I have tried various settings but still very bright or ain’t sharp enough.
Any sifus would like to advise/share your settings? Thanks in advance