I bought and avatar with another user in my playstation, is there a way to use that avatar with another profile in the same playstation?
No, you can't use Avatars purchased on another account even though you are on the same console.
It's one of the few things that you can't use despite being on the same console as the purchasing user who has the same console as his "Primary PS4".
Other things which fall into this category include online passe. (even if you both have PSN but only one of you has purchased the online pass)