Hi @anon90529650, welcome to the Asana Community Forum and thanks for taking the time to share your feedback with us!
Asana time zones are automatically set by your browser’s time zone. If someone assign you a task in the USA, it will automatically recognize that time. I also work with teams in different time zones and to avoid confusion I added my working hours to my profile description. I know it could be a good idea if Asana could recognize the assignee time zone when someone sets the due date.
I suggest you to check this thread for more tips: Due date best practices