There's a handy new Fallout 4 mod available which adds traits to the game. It was created by Cirosan, who brought you the Full Dialogue interface mod.
For fans of the Fallout series lamenting the absence of traits, Cirosan's Traits and More mod will make it all better. Plus, there isn't a two trait limit - you can apply as may as you like.
Here's the mod's description:
"This mod adds a number of new Traits and a few new Perks into the game. Because the standard perk menu (the Vault Boy chart) precludes adding new perks/traits directly, these new perks and traits are obtained by constructing a special item at a Chemistry Station (under the Utility section), then using that item on your character to add the perk.
"Many Traits/Perks are directly inspired by previous Fallout titles, but quite a few are original creations. Also included are items that remove all perks and remove all traits, so if you want to re-spec your character build or want to uninstall the mod, it's only a few clicks away."
Due to script limitations, users will only be able to add traits to their character once they find the Chemistry Station. Not being able to add traits during character creation was the case with earlier Fallout titles. Except for Fallout 3, which like Fallout 4 didn't include traits.
You can download the Traits and More mod over on Nexus Mods. While you're there, you can find out more on the mod and look over the list of available traits.