Albariño (Spain)
Alvarinho (Portugal)
Sauvignon Blanc (France)
Assyrtiko (Greece)
Vermentino (Italy)
Sparkling Rosé
Champagne (France)
Prosecco (Italy)
Cava (Spain)
Sekt (Germany)
Grilled Sardines is typical Spanish. The dish deserves a Spanish white wine with fresh acidity. Albariño is a perfect match. Also note that Alvarinho is the Portuguese name for the same grape.
A French Sauvignon Blanc, like Pouilly Fumé from Loire, will also work very well.
The Greeks would drink Assyrtico.
Italians would drink Vermentino.
Everyone would like a sparkling Rosé.