Here is the full list of all 44 Shadow Tactics: Blades of the Shogun - there are Aiko's Choice achievements.
Collect 17 badges.
Fail the Shrine riddle at the beginning 3 times.
Kill Lady Chiyo without getting a disguise.
Finish all missions.
Listen to everything Kuma has to say.
Find all hidden caves in Hana Gakuen.
Finish “The Secrets of Hana Gakuen”.
Kill Lady Chiyo with any character other than Aiko.
Kill a samurai with a rock.
Use Aiko's disguise 15 times.
Talk to a samurai when disguised with Aiko.
Kill or knock out 5 guards at the same time with all 5 characters.
Kill 30 guards with the help of the environment.
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.”
Distract 50 guards with Hayato's stone.
Kill 3 Samurai with Yuki.
Kill the Captain.
Hide 150 bodies.
Travel 1200 meters in water during the mission “The Best Laid Plans”.
Kill 10 guards with Takuma's Sniper Rifle that are farther than 25 meters away from him.
Kill a Samurai with a flower pot.
Find the perfect spot for sunbathing.
Execute a plan with all 5 characters.
Finish the mission “A Night at Sea”
Kill at least 3 guards in the mission “A Night at Sea”.
Distract 4 guards at the same time with Kuma.
Finish the mission “Reunion at Nagoya”.
Kill all enemies at the mansion in Nagoya.
Kill or knock out 150 guards.
Hide 100 bodies.
Kill or knock out 100 guards.
Come out of the other side of the river in Nagoya.
Hide 50 bodies.
Kill 10 guards with a drop attack.
3 times in one mission, kill 2 guards at once with Mugen's Swordwind.
Kill 20 guards with Mugen's Swordwind.
Kill or knock out 50 guards.
Kill a guard with a drop attack from a rope.
Throw a guard into a well.