For noise, lower is better (Noise Level, THD, IMD, Crosstalk). The higher dynamic range is better.
Picture below is frequency response graph. The more straight graph is the more neutral frequency response it would be. For LG V10, headphone frequency response around 50Hz is slightly high that +0, it's mean that when playback at those frequency would be slightly louder than it should. If the sooner the graph drop at higher frequency, mean the less response in higher frequency. AXON 7 would has better higher frequency response than V10 as you saw from the graph. However, you would found it a bit louder than usual as the graph show.
This could happened from various reasons. When using earphone, some phone route audio data through Equalizer or DSP (Audio FX, Dolby Atmos, Maxx Audio, Viper and such) or have either Software or Hardware issues which make earphones output has non neutral response (like AXON 7 and V10).
Some are not having this problem (eg., Xiaomi Mi Max)
Some people prefer phone that route audio through addition DSP when using earphone, while some are not. I'm the latter.