head to head
Marvel Snap asks more than Codenames, and the gap is variance.

Reads · Pure Mind Games
A team word game about predicting how partners will read your clues.

Reads · Grand Arena
A fast card game where the snap mechanic makes reads central.
Codenames leans Reads (Pure Mind Games); Marvel Snap leans Reads (Grand Arena).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Codenames
No physical skill in giving word clues
Marvel Snap
No execution component
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Codenames
Modeling how teammates interpret your clues is the game
Marvel Snap
Snap/retreat decisions are pure opponent psychology
Marvel Snap leans clearly harder on variance.
Codenames
The fixed board adds little randomness mid-game
Marvel Snap
Hidden locations and draws drive swings
Marvel Snap leans clearly harder on optimization.
Codenames
Some clue-efficiency math underlies the prediction
Marvel Snap
Deck construction and curve still matter
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.