Here is the full list of all 100 Mosaique Neko Waifus 2 achievements. It takes around 1-2 hours to unlock all of the achievements on Windows.
LEVEL UP TO LEVEL 5
COLLECT 2 ITEMS
CLICK THE PUZZLE PIECES 50 TIMES
SOLVE 2 PUZZLES
SOLVE 10 BLOCKS
COLLECT 1 ITEM
SOLVE FIRST PUZZLE WITH SARA
GATHER 2 UNSPENT ABILITY POINTS
SOLVE 1 PUZZLE
CLICK THE PUZZLE PIECES 10 TIMES
LEVEL UP TO LEVEL 2
SOLVE 1 BLOCK
CLICK THE PUZZLE PIECES FOR THE FIRST TIME
HELLO THERE!
SOLVE 5 PUZZLES
SOLVE 10 PUZZLES
SOLVE 15 PUZZLES
SOLVE 20 PUZZLES
CLICK THE PUZZLE PIECES 100 TIMES
CLICK THE PUZZLE PIECES 200 TIMES
CLICK THE PUZZLE PIECES 300 TIMES
CLICK THE PUZZLE PIECES 400 TIMES
CLICK THE PUZZLE PIECES 500 TIMES
CLICK THE PUZZLE PIECES 600 TIMES
CLICK THE PUZZLE PIECES 700 TIMES
CLICK THE PUZZLE PIECES 800 TIMES
CLICK THE PUZZLE PIECES 900 TIMES
CLICK THE PUZZLE PIECES 1000 TIMES
COLLECT 3 ITEMS
COLLECT 4 ITEMS
COLLECT 5 ITEMS
COLLECT 10 ITEMS
COLLECT 15 ITEMS
COLLECT 20 ITEMS
COLLECT 25 ITEMS
COLLECT 30 ITEMS
COLLECT 35 ITEMS
COLLECT 40 ITEMS
SOLVE 25 PUZZLES
SOLVE 30 PUZZLES
SOLVE 35 PUZZLES
SOLVE 40 PUZZLES
SOLVE ALL SARA PUZZLES
SOLVE FIRST NIKO PUZZLE
SOLVE ALL NIKO PUZZLES
SOLVE FIRST SAYOURI PUZZLE
SOLVE ALL SAYOURI PUZZLES
SOLVE FIRST CHEN PUZZLE
SOLVE ALL CHEN PUZZLES
SOLVE FIRST SARA AND SAYOURI PUZZLE
SOLVE ALL SARA AND SAYOURI PUZZLES
SOLVE FIRST CHEN AND SUYIN PUZZLE
SOLVE ALL CHEN AND SUYIN PUZZLE
GATHER 5 UNSPENT ABILITY POINTS
GATHER 7 UNSPENT ABILITY POINTS
VIEW 1 PHOTO
VIEW 2 PHOTOS
VIEW 100 PHOTOS
ALL GIRLS JUMP OUT OF THEIR CLOTHES
SOLVE 50 BLOCKS
SOLVE 100 BLOCKS
SOLVE 200 BLOCKS
SOLVE 300 BLOCKS
SOLVE 400 BLOCKS
SOLVE 500 BLOCKS
SOLVE 600 BLOCKS
SOLVE 700 BLOCKS
SOLVE 800 BLOCKS
SOLVE 900 BLOCKS
SOLVE 1000 BLOCKS
LEVEL UP TO LEVEL 10
LEVEL UP TO LEVEL 15
LEVEL UP TO LEVEL 20
LEVEL UP TO LEVEL 25
LEVEL UP TO LEVEL 30
FINISH NIKO EXTRA PUZZLE
FINISH SARA AND SAYOURI EXTRA PUZZLE
UNLOCKED "PEEK" IN SKILL TREE
UNLOCKED "FLARE" IN SKILL TREE
UNLOCKED "EARTHQUAKE" IN SKILL TREE
UNLOCKED "LOVE SPARKLE" IN SKILL TREE
UNLOCKED "FLIP ALMOST SOLVED" IN SKILL TREE
UNLOCKED "CHOCOLATE AIRSTRIKE" IN SKILL TREE
UNLOCKED "FLASH BOMB" IN SKILL TREE
UNLOCKED "SECRET PRESENT" IN SKI
SOLVE 20 PIECES USING "FLIP ALMOST SOLVED"
CLICK A PIECE WITH "SECRET PRESENT"
CLICK A PIECE WITH "SECRET PRESENT" 5 TIMES
"LOVE SPARKLE" FIRED 50 TIMES
FIRE "CHOCOLATE AIRSTRIKE" 30 TIMES
FIRE "EARTHQUAKE" 10 TIMES
"FLARE" FIRED 15 TIMES
"LOVE SPARKLE" FIRED 10 TIMES
LEVELED 5 ABILITIES IN TOTAL
LEVELED 10 ABILITIES IN TOTAL
LEVELED 15 ABILITIES IN TOTAL
LEVELED 20 ABILITIES IN TOTAL
GAIN 5000 EXPERIENCE
GAIN 10000 EXPERIENCE
GAIN 30000 EXPERIENCE