FR 2508 then FR 4597 at Barcelona
Cologne → Barcelona → Porto
Timetable, Barcelona time
21:45FR 2508 from Cologne at the gate
20:40FR 4597 to Porto leaves the gate
22 h 55 apart on the timetable, overnight
FR 4597 leaves 22 h 55 after FR 2508 arrives on the timetable: more than half a day, so not a connection we count.