Laufey does a ton of things in the first two games, but none of it is posthumous action.
The entire plot of the first two games can be boiled down to how a person who is dead and truly gone, can still be a huge presence in your life through the memories, places, and actions they undertook when they were alive.
Everything we see are things she said and did before she died. Some of it is on a somewhat supernatural level due to her abilities as a giant, but unless I truly missed something, none of it "occurs" after she dies.
In fact this entire new game (that Laufey is "alive" somewhere) directly contradicts what Kratos sees when he steps into the light of alfheim, basically confirming that's where she (or what's left of her) is.