Ascended Fanon: In the first game whenever someone says "Osu" it's always using the Japanese written language, even when an American character says it. In Ouendan 2 whenever an American says "Osu" it is simply spelled "Osu". This is more than likely because most American gamers (including the ones on this wiki) spell the game as "Osu! Tatakae! Ouendan" (as opposed to "Hey! Fight! Cheersquad").
Fan Nickname: Encouraging Nobility for the rival Ouendan in the sequel, since their flag has the letters E and N inside a circle. Sadly, it's most likely just a romanization of the word Ouen (cheer).note It's still a perfectly valid name though, as the Asahi Ouendan are also known as 高潔の応援団 (lit. "The Noble Ouendan")
Alternatively, 'Bluendan' pops up for the rival team, since the most apparent description of them to non-natives is 'the Ouendan team, but, blue.'
Keep Circulating the Tapes: After the end credits of Ouendan 2 the words "Thanks for playing!!" are shown in Japanese AND English. This was likely done as a subtle wink to importers.