pf2e.fyi
From Pathfinder #176: Lost Mammoth Valley, which isn't enabled.

Merciful Charm

ITEM 3
Price 9 gp
Usage affixed to weapon
Bulk —
Category talisman

Activate envision
Trigger You Strike with the affixed weapon
Requirements You're trained in the affixed weapon.

This small limestone pendant is typically carved in the shape of clasped hands. When activated, the affixed weapon gains the nonlethal trait for the triggering attack and all other attacks for 1 minute.

Effect: Merciful Charm

Pathfinder #176: Lost Mammoth ValleyOGL