The following passages are taken from the Accelerant core rules:
"This effect can be used in one of two ways. An Imbue effect with the verbal “Imbue [Trait Name] Trait” will give you the specified Trait for the remainder of the event."
"Otherwise, this effect is some enhancement or extra ability that is described on an Effect Card that is given to you after the effect is used upon you. An Imbue effect with no trait will not take effect until you have read the effect card. Imbue will usually give you some ability that can be used during the current event, although the effect card might describe some effect that lasts beyond the current event. Imbue is a beneficial effect."
"Imbue effect cards can have a wide variety of long term plot effects. Examples include granting a defense against certain types of attack, strengthening the spirit of a dead character, and similar exceptional abilities. If a player can use an Imbue effect, that ability will always have some in game action that must be accomplished before you can use the ability. You might need to gather and mix components. You might need to construct some item from strange parts. These actions earn you the effect card needed to use this effect. You can never use an Imbue ability without the appropriate effect card to represent the properly prepared components."
While it can be beneficial, it is also possible that by gaining a certain trait, that trait may come back to haunt you later even though the trait itself was not directly harmful. Example: if you were imbued with a trait and then unfriendly NPCs came looking for characters who had that trait. Now they're looking for you too.