Cygnus Knights

Do the Cygnus Knights wear regular their regular jobs clothes or do they have their own special uniform?

The former.

Well, they get their own hat and overall, but that's it.
See my avatar for reference. xd

On the subject of Cygnus equipment:
I know they have their own hat and overall but as far as I can tell there are no useful stats on those equips, or am I wrong?
Also despite having their own equips can Cygnus still wear common equips? or job specific ones [i.e. pirate overall]?

Yes they can. As long as their Cygnus job matches that of the equip.

They can wear both, but here are the items exclusive to Cygnus.

From StrategyWiki, the free strategy guide and walkthrough wiki.

Knights of Cygnus can use the same class equips as normal players. A symbol below the character guild and name will symbolize the player's position as a Cygnus Knight.

Noblesse equipment
New Noblesse characters starting in ereb will receive:

• Noblesse Elegant Hat. Require level: 1. Weapon Defense: 3. Not trade-able.
  
• Noblesse Gorgeous Robe. Required level: 0. Weapon Defense: 5. Not trade-able.
  
• Noblesse Medal. Required level: 0. Not trade-able, not sell-able.
  

Medals
You can acquire improved medals after achieving higher levels.

• Training Knight Medal. Required level: 10, +50 HP, +50 MP. Not trade-able, not sell-able.
  
• Official Knight Medal. Required level: 30, +100 HP, +100 MP. Not trade-able, not sell-able.
  
• Advanced Knight Medal. Required level: 70, +150 HP, +150 MP, +1 STR, +1 DEX, +1 INT, +1 LUK. Not trade-able, not sell-able.
  
• Captain Knight Medal. Required level: 120, +200 HP, +200 MP, +2 STR, +2 DEX, +2 INT, +2 LUK. Not trade-able, not sell-able.
  

From StrategyWiki, the free strategy guide and walkthrough wiki.

*drool* Those are some smexy medals. That gives me a extra kick.

They can wear both, but here are the items exclusive to Cygnus.

From StrategyWiki, the free strategy guide and walkthrough wiki.

Knights of Cygnus can use the same class equips as normal players. A symbol below the character guild and name will symbolize the player's position as a Cygnus Knight.

Noblesse equipment
New Noblesse characters starting in ereb will receive:

• Noblesse Elegant Hat. Require level: 1. Weapon Defense: 3. Not trade-able.
  
• Noblesse Gorgeous Robe. Required level: 0. Weapon Defense: 5. Not trade-able.
  
• Noblesse Medal. Required level: 0. Not trade-able, not sell-able.
  

Medals
You can acquire improved medals after achieving higher levels.

• Training Knight Medal. Required level: 10, +50 HP, +50 MP. Not trade-able, not sell-able.
  
• Official Knight Medal. Required level: 30, +100 HP, +100 MP. Not trade-able, not sell-able.
  
• Advanced Knight Medal. Required level: 70, +150 HP, +150 MP, +1 STR, +1 DEX, +1 INT, +1 LUK. Not trade-able, not sell-able.
  
• Captain Knight Medal. Required level: 120, +200 HP, +200 MP, +2 STR, +2 DEX, +2 INT, +2 LUK. Not trade-able, not sell-able.
  

From StrategyWiki, the free strategy guide and walkthrough wiki.

Yea that's where I got my info too, and the hat and overall seem completely useless.

They're, basically. But it's something that sets them apart.

Well only few medals and overall and a hat.
like aran gets few exclusives

Yea that's where I got my info too, and the hat and overall seem completely useless.

I'm gonna make a lukless mage so I'll probably use these because I won't have many options for clothes.