Michael Owen was a hell of a talent at 18, a better player than Marcus at that age IMO.
He definitely relied alot on pace, and he had a very simple dribbling technique, but he was very good in tight confined spaces and kept the ball very close to himself due to that low centre of gravity. He could also beat multiple players at that age and excellent decision-making for his age.
What Marcus has over him is the greater range of skills, set pieces, long range shots, more skills in his locker, physically has potential to become stronger etc. Marcus has more potential for sure, but people heavily underrate Owen at his peak. England's best big match attacking talent since Gascoigne/Shearer IMO... and even after he lost his pace, had zero ability to get past people, he had super intelligent movement off the ball and cold as feck composure in front of goal.
I hope Rashford goes on to become a more complete player than him, but lets hold our horses before we say he's already better than Owen was at that age. Owen at his best, was like a slightly less talented version of an Aguero that we see now, but more mentally stronger and better finisher under pressure.