From Pathfinder Lost Omens Character Guide, which isn't enabled.

Everstand Stance

FEAT 1

Activity 1 action

Requirements You are wielding a shield.

You brace your shield with both hands, enhancing its potential for both offense and defense. When in this stance, you wield the shield with both hands. When wielding a shield this way, increase the weapon damage die of the shield's boss or spikes by one step, and increase the shield's Hardness by 2 when using the Shield Block reaction.

Pathfinder Lost Omens Character GuideOGL