Or you can but there are noticeable differences.
If you compare both of these songs, they are actually a lot different.
Next Level may sound like multiple different songs like O.O, but they constantly have the same mood and same concept for the whole song.
As opposite to NMIXX they have an edgy/dark concept at the beginning and the end of the song. In the middle of the song, they have a cute/bright concept, and the mood changes at that part.
I think NMIXX purpose is not to make the messy song but to mix "cute" and "girl crush" or any other concept together.
