He's impressive for a 19 year old in his first season. Technically and physically he's good at all the basics - runs, passes, dribbling, tackling, effort.
He's definitely not going to make it as a LB at a team like United though - you need to be left footed or excellent at something. He could make a solid RB - but he needs to develop a USP - full backs in the modern game all excel at something. E.g. AWB at tackling, TAA at passing/crossing, Chilwell at runs etc. Even Shaw who doesn't really excel at anything specifically but his fundemental technique and ball retention is a level or two above Brandons.
But I think he could make it at midtable team easily - I'd like to see how he plays as a RB overlapping on his natural right food.