"You are only as good as your last fight." Beterbiev looked a bit his age last time out. Smith on the other hand looked like a 100 bucks. Smith will box well and hold his own, until Beterbiev makes the small adjustments and likely takes him out, but I am leaning towards Beterbiev by UD.
One thing to consider is Canelo´s defense. It makes his opponents second guess themselves and also be weary of counters. Canelo´s opponents always throw less punches against him than is their average. However, Beterbievs own offense could have a similar result, forcing Smith to shell up.