There are several different items to collect in Assassin’s Creed Liberation. Besides those that are easy to discover, there are three types of items that can only be collected when Aveline assumes a specific persona. Voodoo dolls can only be found and pickpocketed by the slave persona, jeweled brooches can be accessed by the lady persona and assassin’s coins can only be looted by Aveline in assassin’s robes.
Voodoo dolls have to be stolen from hougans that are located in different places around the Bayou and New Orleans. Aveline must wear slave’s outfit in order to be be able to locate and pickpocket the hougans.
Jeweled Brooches can be acquired from 10 different gentlemen that are waiting for a lady to cross their path in New Orleans. Once you find them and charm them they will give you a jeweled brooch as a symbol of a never dying love, right? (don't worry, it'll fade quickly)
Smugglers carry around some assassin’s coins that you want to collect. Those specific smugglers can only be located by Aveline in assassin’s robes. You will have to beat or kill them and then loot the bodies to acquire the coins.
Acquiring all persona-specific items will grant you with Persona Collector achievement/trophy. Besides the trophy each persona-specific collection will unlock a new outfit for Aveline. A Charming Dress outfit for a lady, a Chichen Itza Disguise outfit for a slave persona and a badass looking Bayou Hunter assassin’s outfit. The former two are nothing special but the Bayou Hunter outfit is really good-looking and worth your attention.