Himaruya has revealed that one of the reasons there are two characters representing Italy is that during WWII, "Italy was split into two diffetent countries," in which the northern half stayed with Axis while the southern half (partisans who wished to end the war) switched over to the Allies' side.
With this in mind, technically Veneziano was, to some degree most likely okay with Nazi rule, acts and ideas, whereas Romano was not. This means that Veneziano technically probably wasn't into doing partisan work like he is shown to be doing in Auf Wiedersehen, Sweetheart and Locked Away. Romano would be, however, as a part of the Italian resistance.
Random Canon Hetalia Facts
By KrystalWulf
Just some canon facts. Gathered from the anime, manga, Hetalia wiki and HetaFacts. Sometimes Google images. I... More