Here is the full list of all 22 Aokana - there are Four Rhythms Across the Blue achievements.
Completed all routes. There are too many of them.
Can you even see anything?
Become the Super High School Level FC Coach!
Completed the true ending.
Completed the second half of Asuka's route.
Completed the first half of Asuka's route.
Completed the second half of Misaki's route.
Completed the first half of Misaki's route.
Ook! Ook!
Completed the bad end. Do better on the next run!
Completed the second half of Mashiro's route.
Completed the first half of Mashiro's route.
Better luck next time.
Completed the second half of Rika's route.
Completed the first half of Rika's route.
Completed chapter 6 of the common route.
Completed chapter 5 of the common route.
Completed chapter 4 of the common route.
Challenger approaches!
Completed chapter 3 of the common route.
Completed chapter 2 of the common route.
Completed chapter 1 of the common route.