Nevin, boxing for the British Lionhearts, dropped a split decision (48-47 48-47 47-48) to the Italia Thunder lightweight at the Celtic Manor in Newport.
Nevin, who has moved up from bantamweight to lightweight for the WSB, beat Stankovic on a split decision lining out for Paris United in the WSB earlier this year.
But the Serb, who was trailing on points going into the fifth and final round last night, finished strongly to exact sweet revenge over the Mullingar man.
The Moate BC southpaw, who beat Szello en route to gold in the semi-finals of the 2011 European Elite Championships in Turkey, earned a unanimous (50-45 50-45 50-45) decision.
Ward's win made it 3-0 to the Lionhearts following victories for England's Joe Joyce and Wales' Andrew Selby over the WSB defending champions.
Elsewhere, the National Intermediate Championships resume at 10.30 today at Dublin's National Stadium.