Please note, I am just translating this from the Swashbuckler subclass for rogues, as I thought this might be cool for fighters as well. It might be too overpowered, or not powerful enough - I have tried to balance it out, please give feedback so that I can improve it.

You focus your training on the art of the blade, relying on speed, elegance, and charm in equal parts. While some warriors are brutes clad in heavy armor, your method of fighting looks almost like a performance. Duelists and pirates typically belong to this archetype.

A Swashbuckler excels in single combat, and can fight with two weapons while safely darting away from an opponent.

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Fancy footwork

When you choose this archetype at 3rd level, you learn how to land a strike and then slip away without reprisal. During your turn, if you make a melee attack against a creature, that creature can’t make opportunity attacks against you for the rest of your turn.

Rakish Audacity

Starting at 3rd level, your confidence propels you into battle. You can give yourself a bonus to your initiative rolls equal to your Charisma modifier.

Also, once per turn, you can add your Charisma modifier to attack and damage rolls when attacking with a weapon which has the finesse or light property.

Additional Fighting Style

At 7th level, you can choose an additional fighting style out of Dueling or Two-Weapon Fighting.

Dueling

When you are wielding a melee weapon in one hand and no other weapons, you gain a +2 bonus to damage rolls with that weapon.

Two-Weapon Fighting

When you engage in two-weapon fighting, you can add your ability modifier to the damage of the second attack.

Panache

At 10th level, your charm becomes extraordinarily beguiling. As an action, you can make a Charisma (Persuasion) check contested by a creature’s Wisdom (Insight) check. The creature must be able to hear you, and the two of you must share a language.

If you succeed on the check and the creature is hostile to you, it has disadvantage on attack rolls against targets other than you and can’t make opportunity attacks against targets other than you. This effect lasts for 1 minute, until one of your companions attacks the target or affects it with a spell, or until you and the target are more than 60 feet apart.

If you succeed on the check and the creature isn’t hostile to you, it is charmed by you for 1 minute. While charmed, it regards you as a friendly acquaintance. This effect ends immediately if you or your companions do anything harmful to it.

Elegant Maneuver

Starting at 15th level, you can use a bonus action on your turn to gain advantage on the next Dexterity (Acrobatics) or Strength (Athletics) check you make during the same turn.

Master Duelist

Beginning at 18th level, your mastery of the blade lets you turn failure into success in combat. If you miss with an attack roll, you can roll it again with advantage. Once you do so, you can’t use this feature again until you finish a short or long rest.