head to head
Neither is meaningfully harder - they pose close to the same test. The widest gap is execution, and it is a single point.

Execution · Practiced Mastery
A competitive falling-blob puzzle testing fast chaining under speed pressure.

Execution · Pure Mechanics
Battle royale Tetris where raw stacking speed decides who outlasts 98 opponents.
Puyo Puyo Fever 2 leans Execution (Practiced Mastery); Tetris 99 leans Execution (Pure Mechanics).
Tetris 99 leans a little harder on execution, though the gap is small.
Puyo Puyo Fever 2
Fast chaining under accelerating speed is the lead axis
Tetris 99
High-speed stacking and finesse define survival
Tetris 99 leans a little harder on reads, though the gap is small.
Puyo Puyo Fever 2
Versus human play adds light prediction of attacks
Tetris 99
Targeting and badge timing against humans matter mid-match
Tetris 99 leans a little harder on variance, though the gap is small.
Puyo Puyo Fever 2
Piece colors random but quickly mapped
Tetris 99
Incoming garbage timing and piece sequence add chaos
Puyo Puyo Fever 2 leans a little harder on optimization, though the gap is small.
Puyo Puyo Fever 2
Chain patterns have known optimal building techniques
Tetris 99
Stacking theory and downstack efficiency are studied skills
A matching score does not mean a matching test. Two games can both sit at 10 on execution and demand completely different things of you - which is why the reasoning above matters more than the number beside it.