The quest for the stance involves hunting stuff in Occulta Dungeon again. ~_~ Hope it's easy. Anyway the skills are
Con Fuoco
lvl10: dur 180s, +10 aspd, +10 crit, +10 acc
lvl11: dur 198s, +15 aspd, +15 crit, +15 acc, +5% mHP
Virtuoso
lvl10: dur 180s, -10% damage received from monster
lvl11: dur 198s, -10% damage received from monster, +5% mSP
Con Impeto
lvl10: dur 180s, +10 blocking, +10 evasion, 20% chance to ignore magic attacks
lvl11: dur 198s, +15 blocking, +15 evasion, +2 immunity, +5% mHP, 25% chance to ignore magic attacks
Pieno
lvl10: dur 180s, -10% damage received from player characters
lvl11: dur 198s, -10% damage received from player characters, +5% mSP
Totentanz
lvl1: atk 1011%, 100% chance to inflict [Dance of Death]
Buffs are applied to all squad members within 6m and costs 10 Ancient Star Orbs per buff. Totentanz costs 15 Ancient Star Orbs. Not sure what the status does yet.
The buffs seem rather mild compared to Enhanced Tactics, but since this just came out, they'll probably get adjusted before final release in any case.