Momotarou no Umiwashi

Both are WWII propaganda. 

Both are short, very old, black end white movies from ´40s. Both are setted in WWII-like setting and can be interpreted as World War II propaganda. Both have animals in military and both have war planes. 

In both, the story of Momotaro is remade into something completely different, and both fail to make more interesting story. While Momo Kyun Sword is more fantasy and Momotaro is a girl, Momotarou no Umiwashi is historical and serves more as a propaganda during World War II. 

Both anime adapts the legend of Momotarou. While Nihonichi Momotarou keeps the original plot, Momotarou no Umiwashi is more of a World War II propaganda. Both are short, old, black and white movies. 

Both are short, very old, black and white movies from 1930-40. Both show a story about a hero Momotaro that fights eagles on a sea while riding airplane with his animal companions. Both have anthromorphic animals. Both can be taken as anti-america propaganda, but it´s more obvious in Momotarou no Umiwashi.