ehhh, he's been converted long enough and defensively is probably the better part of his game at the moment. The 'converted winger' thing is played up too much with Bellerín, he's definitively a RB and was never going to be anything else at a high level.
What's been most disappointing is how poor he's been offensively and with the ball. He looks nothing like the player he did when he first came into the team. Seems to have lost all confidence and quality with the ball and in decision making.