Here is the full list of all 26 Pixel Puzzles: Japan achievements. It takes around 8-10 hours to unlock all of the achievements on Windows.
All Puzzles Complete!
Tsukubai
Stop The Pop... With A FIsh
Enlightenment Attained
Gardens of Nijo Palace
Himeji Castle Gatehouse
Hiroshima Castle Gatehouse
Akai Hashi
Consciousness Raised
Butsudan
Temple Lanterns
Osaka Castle
Torii
Cherry Blossom Over Water
A Mind In Training
Koen
Nara Temple Gates
Komainu No Enryakuji
Iwakuni Bridge
On The Road To Enlightenment
Urabandai Lakes
Himeji Castle
Red Temple Of Nara
Komainu No Osaka
Zen Garden
Pull It OUT!