Are you talking obedience, conformation,agility?
In conformation, age does not matter as long as he is intact and registered. But, the ear could be a problem, some judges will look at it as a "badge of honor" and let it go, others will disqualify him.One of the leading Siberian Huskies in the country years ago lost the tip of his ear fence fighting. After that, even though the dog was a Champion and has won numerous best in shows, smoe judges dumped him. Then the dog was awarded Best in Show at Westminster.
In Obedience, agility, Rally, he can be neutered, the ear will probably not be questioned but would not hurt to have something from the vet in case it is questioned, and he can compete for performance titles as long as he is registered with AKC. Age does not matter at all, and having titles is not required, just make sure he is entered in the correct class.