I was literally just researching this. Branded don't seem to have any defining traits in the other games, like Soren, besides the brand. Volke was rumored to be a wolf branded but besides that I don't have anything to go by. They have tendencies, scents, and a gruff speaking pattern maybe? and I'm sure I could find some brands for them. Since they aren't full Laguz I don't want to give them the ears and tails, since that isn't something that happens...