It's Friday in US, but Saturday in Korea. On Monday in Korea, you have to wait until the next day for them to work. You only have 1h-2h before the work day in Korea to sync with them in US, only on the West Coast, only 4 days a week.

For “nomads”, I think the more common situation is that the nomad works roughly 2am to 10am Tuesday to Saturday, maybe shifted to 6am to 2pm for half day overlap.

There are no syncing issues this way.

Or just work at off hours. That’s how I’ve always worked with asia-based teams.