The Italians engaged in a number of actions with British Battleships. Their problem was they were relying on long range shooting, sometimes over 25,000 yards. The modern Littorio Class were fine well protected ships, with good 15" guns, but they suffered from a dispersion problem, that degraded their accuracy. The older rebuilt Battleships were poorly protected, and only had 12.6" guns, but they did have 10 of them. Again they were relying on very long range shooting, and without fire control radar their chances of scoring a hit on even a Battleship sized target was very small.
Giulio Cesare at the Battle of Spartivento was physically present. No gunfire from her hit anything AFAIK. The wording is confusing.What British BB fought Italians with 12.6” guns?
The Littorios had good artillery tubes as did the Cavours. It was the shells which proved inconsistent in mass and shape, so their flyout during salvo was not something the Italians could rely to be ballistically predictable in the atmosphere at their preferred long ranges. Such aerodynamic inconsistency was not just an Italian problem as Somerville (or rather Lancelot Holland) discovered during the cruiser action.