Barcelona is 12 hours ahead of Honolulu

There is no standard 8-to-6 overlap. Someone joins early or late.

Honolulu and Barcelona live on different parts of the day. With 12 hours between them, standard working hours simply don't meet. Make the most of handoffs — end-of-day in one city becomes start-of-day in the other, so pass work along rather than meeting live. Note that Barcelona follows daylight saving while Honolulu stays put, so the times above drift by an hour seasonally.