Landships II

There were 12 Japanese destroyers in the Mediterranean based at Malta from 1917, helping the British on anti-submarine convoy duties (two British destroyers, Minstrel and Nemesis, were actually transferred to the Japanese Navy in 1917 as well, bringing the Japanese contingent up to 14). One Japanese destroyer was torpedoed (by an Austrian U-boat, oddly enough) and badly damaged, with dozens of fatalities:

http://www.naval-history.net/WW1NavyJapanese.htm

Sakaki, damaged 11th June 1917, Eastern Mediterranean off Crete - torpedoed once by Austrian 'U.27'. On escort duty, her bows were blown off when many of the crew were forward in the mess hall; 68 men killed. She was salvaged and repaired.

Was the flag-showing cruise in the 1920s Crown Prince Hirohito's cruise of 1921? I only ask because he travelled aboard a battleship (Katori, escorted by her sister, Kashima - they were predreadnoughts, similar in design to the British King Edward VII class) and they stopped off at Malta on the way to Blighty (as well as several other British imperial ports and centres).

Further to the above I find that the Japanese destroyers in the Med recorded some 44 encounters with German and Austro Hungarian submarines in the Med. If any of these led to a sinking I don't have info.

U.27 was designed by A.G.Wesse of Bremen based on the UB-II class (Wesse also provided construction licences for similar boats to Sweden). It was one of the most modern boats in the KuK navy and took part in the battle of the Ontranto barrage in 1917. In 1918 it sank the British steamer SS.Anhui and the Destoyer HMS Pheonix. It was handed over to the Italians after the armistice.

No I don't know exactly what the cruise was for (although Fleet Training appears in the text)  but judging by various photos of Japanese naval officers taking snapshots of each other at Pompeii, in Naples, standing in the amphitheater in Rome,  visiting the Pyramids, Camel riding. attending receptions etc it looks like a large scale 'jolly'. There is a shot of some  officers shaking hands with officials in the Italian Naval Ministry at a lunch. A number of Japanese and Italian oficers with sleeves enveloped in gold rings are present as is the Japanese ambassador (who became Japanese Prime Minister after 1945). One wonders if it was a cover for some Japanese - Italian pre Axis discussions.

Yes I slipped on the ship source - confusion comes from the fact that the Izumo was also on the cruise and she was UK built. These two ships were the largest in the Japanese training fleet.