If he can catch, that's a big plus. When my kid tried out for HS, he caught quite a bit in his LL days but not when he moved to the big field. In Legion, he was mostly a RF, CF and SS. Despite that, he still could handle it and liked catching. His freshman year, he told his coaches he can catch. In his sophomore year, even though he was an OF (did some pitching at the sub-varsity), he caught about 25% of all the games he started in out of necessity. There was no back up catcher and my son went to the coach again to let him know he can fill in. By time he made varsity, they had two catchers but he could've caught varsity if they needed him.
It can only help if a player can play multiple positions.
Also, hs coaches have singled out his hustle and his attitude on more than one occasion including an opposing team head coach. One of the team parent's captain came up to me one day during a game and asked if so-and -so was my kid and I said he was and he said that he was fun to watch because he plays hard and has a great attitude. These types of things can give a player an edge during competitive tryouts.