Their English pronunciation and intonation seem a bit off, and it's sometimes hard to catch what they're saying in the English lyrics because it sounds like they're mumbling.
I'm not a native English speaker either, and my English isn't perfect, but it wouldn't hurt for the company to provide more training in pronouncing English lyrics. They don't need to sound like native speakers, just make sure the lyrics are clear and not rough to the ear. Singers in my country practice a lot to get their English lyrics right, even if they can't even speak in that language or understand it. Yet, they put a lot of effort to ensure their songs sound smooth and their pronunciation are clear especially for those who speaking that language.
K-pop is going global, and they're releasing more English songs and lyrics. These idols don't have to be English experts, but it would be great if the company put in a bit more effort. Aespa's "Better Things" is a good example of clear and smooth pronunciation, even though there are clear differences between Giselle and the others. If I'm not mistaken, only Giselle is fluent in English, but in that song, the other three also suprisingly did a very good job with their enunciation.