FR 3194 then FR 4545 at Barcelona
Riga → Barcelona → Porto
Timetable, Barcelona time
23:45FR 3194 from Riga at the gate
21:15FR 4545 to Porto leaves the gate
21 h 30 apart on the timetable, overnight
FR 4545 leaves 21 h 30 after FR 3194 arrives on the timetable: more than half a day, so not a connection we count.