Asus PA27JVC 5K monitor - calibration

#1
The DxO Wide Gamut color space is their internal working color space (their “old” color space was Adobe RGB = now called legacy). DxO WG enables you to export to any desired color space. If in doubt, use soft proofing to preview the result.

#2
Had read the specs of your monitor, but don’t know how those profiles are stored. I assume that “Native” is the maximum what your monitor can show.

If you like check here … for color space comparisons and here … for proven test charts.

BTW, I use custom monitor profiles for 5900K and 6500K, each for sRGB, AdobeRGB, and Native (= close to AdobeRGB + DCI P3 combined), all with 80 cd/m². I’ve also reduced the contrast to about 1:500, which not only suits the comparable low paper reflection but is also easier on my eyes.