I couldn't finish 'em. Looks like this's gonna get complicated.
Sworddancer is a difficult opponent mostly due to her most dangerous attack Deathly Dance which she will use at the start at of the battle and once every few turns which will put the party under the Doom status giving them 10 in-battle seconds to defeat her before the party is wiped out. She mostly uses physical attacks like Pox which will attack the whole party for 2000 damage and above as well as decrease their Defense, Mystery Step which hits the around 1500-2000 and possibly inflict Paralysis and her signature Sabre Dancer to inflict 3000-4000 damage on a single character. She at times counters with Drain Samba and Osmose Dance and casts Temptation a few times to inflict Confuse on the party.
Due to the narrow margin of time the party is given to defeat her, the player is more than likely forced to kill some of his own party members and then revive them so as to extend the duration of the battle. At least two healers should be brought so that they can revive the rest of the fallen party after they die. Seers are a good option due to Arise, although a Summoner and a knower of White Magic also helps, the former can use Phoenix and the latter can heal the party.
Sworddancer doesn't have notable defenses so at this point of the game, most attacks should strike her for 2000 and above damage each. However Sworddancer is fast on her attacks and before long she will re-use Deathly Dance so the player should inflict as much damage as possible before being forced to kill their party again. Equipment like Chouchous, Ribbon, Peace Ring and Red Shoes are mandatory to prevent Temptation from undermining the player's efforts at any given them.
Attackers like Ninja, Archer or Monk are very good as their skills can inflict major damage, especially the Ninja with his Dual Wield ability that will make any physical attack strike twice (including F-Abilities). The Archer is useful as it can strike any character (even those the party seeks to kill) for full damage thus making the process easier. The Monk if possible can use attacks like Phantom Rush or Final Heaven to inflict great damage.
Casting buffs is unwise, as they won't last long and may imperil the player whenever they need to kill their party members, also Haste accelerates the counter. Also while tempting, the idea of either stripping the characters to kill (likely the healers so that they can resurrect everybody in top condition) or placing them on the front row is not recommended as Sworddancer will easily kill them before the player can perform any resurrection. If somehow a character dies before Sworddancer casts Deathly Dance, they should let it remain dead until after she uses it, so that it avoids the Doom status.
Another perhaps more risky and unorthodox way to approach her is to begin the battle with everybody (sans the healers) dead thus they can revive the party instantly and use precious time to inflict as much damage as possible and revive the healers when they perish. Doing so can give the player a much more efficient use of time and give it ample time to damage Sworddancer before her second Deathly Dance, at which point the battle should be manageable enough. If the player's party can inflict enough damage, they can finish the battle before the second Dance kills their party. However the healers are left on their own to take the full brunt of her attacks so they should be able to survive the onslaught long enough to revive and heal the party or the tactic will fail.
All in all this a battle of patience and the player shouldn't be shy of using some items like Phoenix Down or even Elixirs to heal quick as Sworddancer is relentless.
Sword dances are recorded from throughout world history. There are various traditions of solo and mock battle sword dances from Greece, the Middle East, Pakistan, India, China, Korea, England, Scotland and Japan. Many believe that sword dancing evolved from the early Chinese art of wu shu. The simple martial art became a military training technique with swords and spears and then turned into an elaborate acrobatic dance.