So I landed in ICN, and since I was with my wife, it wasn't too difficult as I was treated as a Korean. Which means that they only ask for the symptoms, and after that, they take the temperature. No red flag for us, so they let us have an interview and we downloaded a self diagnosis app, where you have to put a Korean address and a number. They use that number to call the person and ask about you, the relationship, the full address, etc... it's actually pretty thorough. Once everything is checked, they fill the application and set the location on the app for gps tracking.
When you come from the US, you are allowed to connect in a car with your family as long as everyone has a mask. So my brother in law could come and pick us up. He had to come to the gate
#12 and verify himself. And then we transferred to GMP.
From there, flight to CJU where you have to provide a paper that says that you passed protocol and are allowed to travel to the check in counter.
Once you land in CJU, you fill another piece of paperwork. I think I must have given the address for the quarantine at least 5 times, maybe more. And then, you do your PCR test. They send you the results the next day. All negative for both of us. That's it!
And here too, your relative can come and pick you up with a mask.
Also, I was "lucky" that I understood and can write Korean. I am not sure how someone who doesn't speak much of Korean would be able to handle the whole thing. It didn't seem very international, but maybe I am just not aware of what's prepared for foreigners.