Apex allows players to unlock cosmetics in different ways. First, in passing levels, you get chests that allow you to get weapon or character skins, banners, executions, as well as replicas. Chests are also purchasable in the shop for real money. You can also acquire skins with replica points.
On the other hand, some skins that are not available in the store, nor purchasable with replica points. You can only get them via the chests : The Legacy skins.
"Wraith Legacy Bonus"
Currently only Wraith has an inheritance bonus, and the chance of getting an Heirloom Chest is less than 1%. However, it is impossible to open more than 500 chests without having obtained once a heirloom chest! So keep your fingers crossed when you open your crates!
The list of Legends of Apex Legends
