system
Given the following post, respond as if you're commenting on Reddit:
human
[LOTR] Why did Elrond not reforge Narsil and give it to Aragorn at Rivendale before setting out with the fellowship?

Narsil is just sitting in a Rivendale chapel in pieces.

Elrond knows his smiths can reforge the thing.

The fellowship is leaving on an insanely dangerous quest.

He knows Aragorn can call on a vastly OP ghost army with the sword, should he need it (would probably help get those hobbits to Mt Doom).

Why wait until the last minute? He just cranky his daughter got a crush on this man meat?
gpt
In the books he did. In the movies it was because he didn't want to acknowledge Aragorn as the king because that meant he'd have to give his approval to court his daughter which would mean eventually losing her (Elrond is immortal and if Arwen chose to stay with Aragorn he would eventually outlive her).