The Alpino we toured was operated by the Italian Navy (Fincantieri is an Italian company), and therefore if the US purchases the Alpino design, it will equip the ships with its own systems.
The US has already decided that the two 76mm guns on the bow and stern will be replaced by 57mm Mark 110 guns, and that there will be 32 multi-functional VLS tubes instead of 16.
The US has not yet determined which other systems will be onboard, but Hunt said that the Navy might even consider putting high-energy lasers or a rail gun on the frigate.
Source: Fincantieri