A maula pistol dart might bounce off Ezio's armor but blocking it with a swipe would require either a REALLY thing blade (which he does not have) or superhuman reflexes and precision.
The Weirding Way is use of absolutely top-grade fighting skills, one that lets people with Bene Gesserit training beat Sardaukar and Fremen. Use of the Weirding Way is basically "What if every time I fought, I fought in what is literally the most perfect and exact way possible?"
Same logic applies here to dodging a bullet. You can't dodge a bullet unless you're Sonic the Hedgehog. You
can dodge someone's aim. If Ezio knows he's being shot at, he can dodge Paul's aim (although Paul does still have decent combat training by the start of the book).
Weirding Way = Top class fighting and assassination skills.
Master Assassin = Top class fighting and assassination skills.
Shall we declare that particular point even, then?
Paul comes in with a Holtzmann shield - can't be hit by fast-moving objects, lasts 15 minutes+ before suffocation (based on the Idaho analysis above). Full body coverage, 'vulnerable' to energy weapons (the shield just blows up, and takes everyone with it - suicide attack).
Ezio comes in with Altair's armour - can be hit by fast-moving objects, not total coverage, but essentially made out of applied phlebotinum (unknown light, strong alloy) and can stop most steel weaponry. Effect of energy attacks unknown, but probably only as effective as normal breastplates (not terribly).
I think we're playing up the effects of the Holtzmann shield a bit. Paul has a advantage in terms of full body coverage, but if Ezio has better experience using his armour he may be able to compensate. Short term, Altair's armour will block most melee attacks (with human strength) about as effectively as the Holtzmann shield. Over a longer period, denting and armour damage will become a problem, but at the same time Paul's going to start getting worn out by air shortages in the shield. This could end up being a question of stamina.
If either of them can get the drop on the other, they will possibly win. Paul can shoot Ezio with a poisoned dart to win (Ezio carries no antidoes), or Ezio can simply hidden-blade kill Paul if he can get close enough (or shoot him with the hidden flintlock before he puts the shield up/hit him with a throwing knife, depending on distance and preference).
So I suppose the question I want to ask is - who has the superior stealth training here?