Here is the full list of all 27 Shieldmaiden: Remix Edition achievements.
Kill 5 enemies in a single Special Atack
Find the Book
Find the Ribbon
Complete Warden's Sanctuary - Promenade
Don't let the Wardenash create a lotus on the ground
Find the Newspaper
Find the Sprout
Pet the dog
Complete Modigard Main Terminal
Make de Shield hover around Asta for 10 seconds
Defend from a projectile during the wall slide
Kill the Passing Onslaught (the flying enemy inside the Cataclism)
Complete Warden's Sanctuary - Historical Area
Complete Downtown - Commercial District
Complete Downtown - Scrapyard District
Complete Mt. Runa - Hospital
Complete Mt. Runa - The Edge of the Dome
Complete Dome of the Cataclysm
Complete Escape from the Dome
Find the Telescope
Find the Poster
Find the Glasses
Find the Microphone
Find the Stuffed Bear
Find the Frame
Find the Police Cap
Find the Globe