The following article may help with your question: https://www.pctipp.ch/tests...
My experience with the LG UltraFine 27MD5KL-B now shows that the red tones are displayed a tad too brightly. When I have my MacBook Pro next to the 5K LG screen, the LG UltraFine 27MD5KL-B appears slightly warmer (as described in the article). If the colours are really correct, then a calibration is probably unavoidable - although I don't know whether there is a calibration for this monitor (then the operating system probably still plays a role) ... I would also be interested in the calibration!

The colours are similar to those of a built-in Macbook display. The brightness of the screen is also very good. Since it was the only screen Apple sold in the Apple Store for several years, I assume that it is "approved" in terms of quality. And also in digital agencies it was the defacto standard because 5K Retina Display. I only use the screen for websites and can't judge how it fares with print. I got the screen mainly because of the resolution, as there was nothing comparable. Now, of course, there's also the Studio Display from Apple.