Yes, Samus recharges her shields and missile ammo through life-energy left behind by fallen enemies. The wraith blade isn't the same thing. It's still attached to Raziel, therefore the soul-energy that makes up the wraith blade is still "in use".

Personally, I'm not sure Samus' Power Armor could withstand attacks from Raziel's wraith blade at all. Raziel's Reaver has shown the ability to destroy energy barriers and cut through energy barriers. Her energy shield may be magical in nature (again, that original quote of mine was complete speculation), but all that means is that the Reaver might not be able to cut right through her shields. The Reaver will still do damage, just maybe not critical damage on every hit.

Samus' best advantage is the fact that her shields will most likely downgrade the Soul Reaver's effect from "ungodly killing machine" to "moderately harmful weapon". She still has very little in the way of melee attacks, and if she tries to distance herself too much, she could find herself in trouble if locked up in Raziel's TK.

Then again, it's entirely possible that she's got him outclassed. While she's not a melee specialist, she does have melee capabilities, ala Smash Bros. Melee. She's more than capable of putting up a moderate melee fight, but in comparison with Raziel's melee abilities, she doesn't have much to offer.

Her ranged attacks are her advantage, and considering how much she weighs (the suit is fucking heavy) if she stays on the ground, it might be tough for Raz to toss her around with TK. However, if she finds herself airborne, she might be in a pickle. There's no real way to know if Samus' Screw Attack would defend her from a TK attack in the air. Yeah, it defends her from outside interferecne, but Raziel isn't tossing projectiles at her, he's manipulating her entire physical form. So, TK in the air is a toss up. Either the Screw Attack would defend her against it, or it would do nothing to help her.

This is a tough call for me, personally. I honestly don't know who I think would win. They're both very evenly matched. Samus' defenses could possibly cut the effectiveness of the Wraith Blade down substantially, then again, her defenses could do nothing. Her Screw attack may defend her completely from aerial TK manipulation, but then again it might not do anything at all. Raziel is great at melee combat, but aside from his TK, his ranged abilities are lacking. Samus is a master of ranged combat, but her melee abilities aren't much compared to Raz.

I honestly don't know who would win this. Considering the nature of the arena as well, this fight could go on literally forever. Both combatants can revitalize themselves by fedding on the leftover life force of a dead creature, and considering that this arena shifts constantly between different locations and different time periods, they have a nearly limitless number of hosts upon which to feed.

I suppose the deciding factor is who would be willing to use innocent people to further their own goals, and frankly, I'm not sure either would be willing to. Samus isn't a murderer, and Raziel's personality has changed drastically since he was a bloodthristy vampire.

It's a tough call. I'm glad that I am not judging this one.