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.
Komainu No Osaka
Stop The Pop... With A FIsh
Zen Garden
Pull It OUT!
All Puzzles Complete!
On The Road To Enlightenment
A Mind In Training
Consciousness Raised
Enlightenment Attained
Red Temple Of Nara
Himeji Castle
Urabandai Lakes
Torii
Osaka Castle
Komainu No Enryakuji
Iwakuni Bridge
Nara Temple Gates
Koen
Cherry Blossom Over Water
Temple Lanterns
Butsudan
Hiroshima Castle Gatehouse
Akai Hashi
Gardens of Nijo Palace
Himeji Castle Gatehouse
Tsukubai