Costa isnt that usefull with the ball at his feet to be honest, he must be the worst dribbler i've ever seen, and boy does he like to dribble, the amount of times he loses the ball in a completely unnecessary manner is absolutely infuriating. His aerial game is aso very weak for a man of his size. When he is on his game he's got good hold up play and his passing in pretty decent i'd say, but when he is not on his game( which is happening way too often lately), he is a complete liability. He doesnt have much apart from his goalscoring ability, so i wouldnt say that Costa is an ideal CF for us, even though he scores alot. Morata fits the bill alot better, but his goal output is laughable for a supposed top striker, and at the end of the day, goals win games, and unfortunately, Morata doesnt score enough of them, which is why Emenalo is pushing for Lukaku IMO