Enshida is the trainer who seems to follow you around Hoenn, he claims to be on a search for the best trainers
He seems to have a house on the Battle Frontier where he likes to keep track on the best trainers. If you talk to him after beating the 7 Battle Frontier events (Silver Badges), he will give you a Lansat Berry
If you talk to him after beating the 7 Battle Frontier events (Gold Badges), he will give you a Starf Berry