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