The US version of the LG G6enjoys wireless charging, but it won't come with 32-bit Hi-Fi Quad DAC (Digital to Analogue converter)on board, which improved the audio quality. From what I've heard and read, the LG G6 with the on board Hi-Fi DAC will only be available in Asian markets like in South Korean. The reason for that is because the Asian market has a higher and strict demand for better audio performing smartphones. This is according to a research LG has done and the results are in front of you.
I don't know why just not give both US and Asia to enjoy the feature. I went to the LG USA site and the South Korean website and checked the pages for the LG G6. Indeed, the US website doesn't mention anything about Hi-Fi, whether lge.co.kr mentions Hi-Fi Quad DAC. In my opinion, the sound quality isn't less important than the screen quality. Both contribute to the immersion when watching movies on the go or playing Android games, and it's always great to have a phone that brings a better portable Hi-Fi audio experience. When you drop this feature from an entire region, you are just leaving behind millions of users that would have loved to have a great audio experience in the new flagship phone, especially after paying a premium price for it.
This Quad DAC has support for FLAC, DID, DIFF and ALAC file formats. This Quad DAC also supports headphones with in-ear monitors. This new Quad DAC also controls the left and right sound channels separately and promotes crystal clear audio quality with reduced static noise and very low sound distortion (0.0002% sound distortion rate). There is also a nice audio equalizer with Gain, LCF, LMT and even wind noise filter that you can control while recording videos.
If you live in South Korea, you are certainly going to get the one with the new Quad DAC. This feature isn't going to be available in South America nor MEA as well, which again, is very unfortunate.
It's certainly a noticeable advantage for the LG G6 for the South Korea version of the phone. If you are just using the phone for making calls, managing your day, reading emails and play a game once in a while, it's not a big deal, but for other people who playing lots of games, watching movies and love listening to music, this is a disappointment. By the way, the LG G5 has a Hi-Fi Plus Hi-res Audio Module that you can use to improve the audio quality. This is one of the advantages of the G5 modular design, is that you can add features that you want, but LG ditched the modular design in the G6.