What's the better weapon between these two for her? (I changed my build from my last post:>).

Current stats:

Farming for these Wedges was so tiring. I still need to unlock the 8th Demon Wedge slot so i can fully complete her build, and currently, i'm crafting her Siren's Kiss cuz i think it's good for her.

Can someone please tell me how to get this chest, i'm currently on a treasure hunt for chests to get my Trial Rank up.