FR 4584 then QR 3590 at Barcelona
Porto → Barcelona → Firenze
Timetable, Barcelona time
18:55FR 4584 from Porto at the gate
16:45QR 3590 to Firenze leaves the gatealso IB 5374, LL 5374, VY 6074
21 h 50 apart on the timetable, overnight
QR 3590 leaves 21 h 50 after FR 4584 arrives on the timetable: more than half a day, so not a connection we count.