Can you easily distinguish foreigner pronunciation in Korean?

As a native Korean speaker, I am curious if foreigners can easily distinguish Korean pronunciation when speaking Korean. I, as a native English speaker, can distinguish non-native English pronunciation about 95% of the time. The reason I am asking this question is because two members of my favorite Kpop group NCT 127 are from North America, and I wonder if their American pronunciation stands out when they speak or sing in Korean, or if they have naturally adapted after living in Korea for a long time. I have the same curiosity about the Japanese member. So, is it possible to master perfect Korean pronunciation?