Outfits and Headgear are cosmetic only items. You can select 1 out of 4 outfits at the character creation screen. You can obtain outfits by completing some Pursuits, some Missions or purchase them from the game store.
Outfits are the entire appearance from the neck down and Headgear is the head only.
41st Century Agent
Outfit
Part of the 41st Century Agent Costume Pack released October 2015.
Transferred if owned in Defiance Classic
7th Legion Ronin
Outfit
7th Legion Supply Crate from the 7th Legion Faction vendor at Overpass.
7th Legion Samurai
Outfit
Transferred if owned in Defiance Classic
Abominable Warmaster
Outfit
Abominable Warmaster Pack during Solstice Strike.
Transferred if owned in Defiance Classic
APS Envoy
Outfit
Defiance Store: Special Delivery Lockbox
Transferred if owned in Defiance Classic
Ark Alliance Terranaut
Outfit
Powertech Lock Box from the Defiance Store.
Rewarded from the Season 3 on SyFy Pursuit.
Trion Creator Program Giveaways
Ark Infiltrator
Outfit
Rewarded from pre-ordering the Digital Deluxe Edition
Badlands Ronin
Outfit
7th Legion Recruit Kit lockbox granted with DLC purchase.
Biohazard Battler
Outfit
Chance from Biohazard Lock Box from the Defiance Store.
Bubblegum Killer
Outfit
Chance from Corporate Espionage Lockbox
Transferred if owned in Defiance Classic
Castithan Machinist
Outfit
Machinist Supply Crate from the Defiance Store
Castithan Survivalist
Outfit
Survivalist Supply Crate from the Defiance Store
Castithan Veteran
Outfit
Veteran Supply Crate from the Defiance Store
CDC Eradicator
Outfit
Transferred if owned in Defiance Classic
Stratotech Defiance 2050 [Source]
3PL9 WDFG DKPR 9LE7 P7Y7 [Redeem]