This story takes place before the Events of World War II that will lead to main story "The Great War of Archimedes"

1st Installment:

The Princess and the Pilot x The Wind Rises: The Legend of the Mitsubishi A6M Zero.

This story about designer of Zero Fighter was Jiro Horikoshi and his life, when they came from timeline into the Timeline. They will learned about Mitsubishi A6M Zero's Legend.

2nd Installment:

Touhou: Second Sino-Japanese War.

When Sakuya and Makou accidentally time travel too far into 1931, They encountered Japanese Men from Imperial Japanese Army. As the Years goes by, They conquered Manchuria for the Oil and rare Supplies next is The Japanese Army are fighting war against China to establish and expand the Empire. They realized that they traveled to 1937. War against China known as The Second Sino-Japanese War.

Final Installment:

KanColle: The Great War of Archimedes

The Prequel of the Same Name: the story takes place in 1930s When a young naval officer and math prodigy uncovers a conspiracy regarding the construction of Japanese warships for the ongoing World War II, Meanwhile Girls from KanColle Timeline when They heard that they planned to build Largest battleship: the Yamato. In the headquarters of the Imperial Japanese Navy sets out to build the world's biggest battleship Yamato. Rear Admiral Isoroku Yamamoto is opposed to that plan. Isoroku Yamamoto attracts Tadashi Kai (Masaki Suda) who is a genius mathematician. Tadashi Kai discovers discrepancies related to the estimated cost to build the battleship. He tries to uncover a conspiracy in the military with the help of the KanColle girls.