A3 710 then QR 4704 at Barcelona
Athens → Barcelona → Porto
Timetable, Barcelona time
10:25A3 710 from Athens at the gate
08:35QR 4704 to Porto leaves the gate
22 h 10 apart on the timetable, overnight
QR 4704 leaves 22 h 10 after A3 710 arrives on the timetable: more than half a day, so not a connection we count.