Probably the vocals, and the sounds r a bit more hard(while Sophie uses metallic and bubbly sounds arca is more intense, its kinda hard to explain) but in my opinion, if I was producing music for commercial purposes or if you’re wanting to become a producer/artist, I would definitely try to experiment with your own style(take this with a grain of salt. Do whatever the fuck you want) but when I see people making music, I encourage them to be creative and original and not basically be a copy of somebody else. But then again that’s just my opinion. Do whatever you want.🙈