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