This subclass was heavily inspired by the Purple Dragon knights of Dungeons and Dragons Online, and as such all it's abilities are named after theirs. It takes after the traits of a paladin, just without the spellcasting and with more yelling.
Also I just found out Banneret exists after making this.

Purple Dragon knights were the officers and warrior elite of the Cormyrian army, the bulk of which was known as the Purple Dragons. Being awarded knighthood within the Purple Dragons was a great honor for anyone from the forest country. Purple Dragon knights were excellent soldiers by any measure, with intense martial prowess that exceeded most enemies they were likely to face. But more important than their own physical strength was their ability to command, and Purple Dragon knights were not only the best soldiers in Cormyr's service but its most impressive leaders as well. As such, Leadership capability was a major aspect of the training a knight receives.

Cormyrian Knight Training

When you choose this archetype at 3rd level, you gain the ability to use charisma or strength (whichever is higher) to hit and damage with any weapon you are proficient with, so long as you attune to it. (Attunement requires you spending a short rest focused on only that item while being in physical contact with it. In this case, the physical contact will take the form of weapon practice.) In addition, so long as your charisma modifier remains higher than your strength and you attune to a weapon, you can also use your charisma in place of strength for the strength requirements of heavy armor.

Purple Dragon Aura

Beginning at 7th level, whenever you or an ally within 10 ft. of you must make a saving throw, they gain a bonus to the saving throw equal to your charisma modifier (with a minimum bonus of +1). You must be conscious to grant this bonus.

Rallying Cry

Starting at 10th level, you can use your bonus action to inspire your allies with a rallying cry. You and all allies within 10 ft. have the frightened condition removed from them, and they gain 10 extra feet of movement for 1 minute. This ability can be used a number of times equal to your charisma modifier (minimum of 1), and regains all of its uses at the end of a long rest.

Final Stand

At 15th level, you may use a bonus action to give you and all allies within 30 ft. of you temporary hit points equal to your intimidation score, and you gain resistance to all physical damage for 1 minute. You cannot use this ability again until you finish a short or long rest.

For Cormyr!

At 18th level, your Second Wind ability is improved, and will now heal you to full health when used. Additionally, you can now use one of your uses of Rallying Cry to instead give you and all allies within 30 ft. a bonus to weapon damage equal to your intimidate score for 1 minute.