Battle CG anime based on the Zoids Wild franchise. (Source: ANN)

A Ripple in Time Turns the Crucial Tide of WWII. Scheduled for routine military exercises, Commander Kadomatsu and the crew of Japan's newest and most modern Battlecruiser, The Mirai, are ready to test out the ship's state-of-the-art Aegis System. Instead, they find themselves transported back to June 4th, 1942—date of the crucial Battle of Midway, where the Japanese fleet was dealt a crippling blow. When an overzealous Kadomatsu rescues one of the battle's victims, Kusaka, from a sinking zero fighter, the Mirai's fate is sealed. The crew pledges not to do anything to alter the past further. However, they're now forced to fight a U.S. submarine in a battle that should never have occurred. Thus setting off a chain of events that may forever change the flow of history! (Source: Geneon Entertainment USA, edited)

Alternative timelines of plot points from Zi Chuan.

Natural disasters have devastated planet Zi, killing off almost all life. A thousand years later humans have gradually re-established civilization, salvaging ancient Zoids through diving and mining efforts. In a village whose most previous item is a giant sword which they worship as a holy symbol. A teenage boy discovers an ancient Liger-type Zoid while on a deep water salvage operation. Suddenly the village is attacked by skeletal Bio-Zoids intent on stealing a powerful generator located in the village. Our teenage hero awakens the Liger and discovers that the town`s sacred sword is the Liger`s weapon, together they fight off the mysterious Bio-Zoids. At least for now... (Source: AniDB)