This site names Pantothenic Acid specifically for hydration-barrier support — worth a standalone look at this one role, distinct from the site's existing combined explainer.
Pantothenic Acid, as d-calcium pantothenate, is described as positioned to stimulate production of lipids that reinforce the skin's natural moisture barrier, aimed at plump, hydrated skin that resists dryness — a distinct mechanism from B6's separate oil-balance role.
S. Whitmore's featured quote specifically describes skin feeling less tight and dry — worth reading that individual account as one data point relevant to this ingredient's stated role.