Prague is 7 hours behind Osaka
Best overlap: 3:00 PM to 6:00 PM in Osaka is 8:00 AM to 11:00 AM in Prague.
If you set up a recurring sync, 3:00 PM to 6:00 PM in Osaka (8:00 AM to 11:00 AM in Prague) is the natural home for it. Prague is 7 hours behind Osaka, leaving about 3 hours of daily overlap — enough for most meetings if you don't leave them too late in the day. These times hold for most of the year, but Prague's daylight saving (which Osaka doesn't use) shifts them by an hour twice annually.