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

Formation Training

FEAT 5

Prerequisites trained in all martial weapons

You know how to fight in formation with your brethren. When you are adjacent to at least two hobgoblin allies, you gain a +1 circumstance bonus to AC and saving throws. This bonus increases to +2 on Reflex saves against area effects.

Effect: Formation Training

Pathfinder Lost Omens Character GuideOGL