Here is the full list of all 44 Shadow Tactics: Blades of the Shogun - there are Aiko's Choice achievements.
Listen to everything Kuma has to say.
Find all hidden caves in Hana Gakuen.
Kill Lady Chiyo with any character other than Aiko.
Talk to a samurai when disguised with Aiko.
Fail the Shrine riddle at the beginning 3 times.
Collect 17 badges.
Kill 10 guards with Takuma's Sniper Rifle that are farther than 25 meters away from him.
Find the perfect spot for sunbathing.
Kill or knock out 5 guards at the same time with all 5 characters.
Execute a plan with all 5 characters.
Kill 3 Samurai with Yuki.
Come out of the other side of the river in Nagoya.
Distract 50 guards with Hayato's stone.
Kill at least 3 guards in the mission “A Night at Sea”.
Kill 30 guards with the help of the environment.
Kill Lady Chiyo without getting a disguise.
Distract 4 guards at the same time with Kuma.
Finish all missions.
Finish “The Secrets of Hana Gakuen”.
Use Aiko's disguise 15 times.
Kill a samurai with a rock.
Hide 150 bodies.
Kill 10 guards with traps in Hana Gakuen.
Hide with all characters in a single bush.
Finish the mission “Red Lights at Matsuyama”.
Don't extinguish any light sources in Matsuyama.
Finish the mission “The Best Laid Plans”.
Don't kill anyone with Takuma during the mission “The Best Laid Plans.”
Kill the Captain.
Kill a Samurai with a flower pot.
Travel 1200 meters in water during the mission “The Best Laid Plans”.
Kill or knock out 150 guards.
Hide 100 bodies.
Kill 20 guards with Mugen's Swordwind.
Finish the mission “A Night at Sea”
Finish the mission “Reunion at Nagoya”.
Kill all enemies at the mansion in Nagoya.
Kill or knock out 100 guards.
Hide 50 bodies.
Kill or knock out 50 guards.
Kill a guard with a drop attack from a rope.
Kill 10 guards with a drop attack.
3 times in one mission, kill 2 guards at once with Mugen's Swordwind.
Throw a guard into a well.