EW 2520 then EW 521 at Barcelona
Stuttgart → Barcelona → Cologne
Timetable, Barcelona time
14:25EW 2520 from Stuttgart at the gate
13:25EW 521 to Cologne leaves the gate
23 h apart on the timetable, overnight
EW 521 leaves 23 h after EW 2520 arrives on the timetable: more than half a day, so not a connection we count.