Wew this is about to happen. Didn't know One Piece vs Fate was this popular.
I'm voting for Whitebeard and here's why.
Kenbunshoku Haki is gonna give him a serious edge here due to this version of Arturia lacking instinct in this forum. Which is going to limit her in this match. Kenbunshoku is also versatile seeing as how it will allow the user to know the strength of the opponent, sense negative emotions, see and "hear" the future to predict the enemies attacks and gives the user a 360% view of the battlefield.
He also easily destroys her in terms of stamina, endurance and has a higher pain threshold allowing him to outlast her with ease. Whitebeard is superior to characters such as Ace who can fight for 5 days despite being at twice the advantage due to Jinbe incorporating Water and Haki into his attacks. He is also superior to Akainu and Kuzan who managed to fight for an entire 10 days before a winner was chosen. Whitebeard was able to fight on with a heart attack during marineford, got a stomach filled of Magma, half of his face blown off and still managed to clap Akainu. After that he nearly killed Blackbeard and was only stopped by getting ganged up by the rest of BB's crew. And he still had enough to give a speech before finally dying.
As i pointed out in a different thread her magic resistance isn't doing anything here. We do not equalize Devil Fruits or Haki to Magic, Ki, Chakra etc. Nothing in his arsenal can even remotely be compared to magic.
Also i am unsure about her natural durability, her profilers states that she only has that durability via barriers. And if her natural durability is only mountain level she's going to get one shotted. And unlike Arturia Whitebeard has striking strength that matches his AP and durability.
Also does that horse scale to her AP or durability? If not then if that horse gets damaged she's screwed.
Shirohige takes this 6/10 times due to his immense stamina advantage, precog, higher natural durability and non magical attacks.
However,the barrier that Artoria summon is very strong,its take a 10 shot of dendera light bulb who is equal to solar flare of sun and a freacking pyramid,so i don't think Shirohige can destroy the barrier so easily.
Hit me up with the calc giving her 20 teraton AP, Whitebeard should be massively superior to the likes of Fujitora who performed the 7 teraton feat with ease and without the Aid of Busoshoku Haki. Akainu himself should be a good deal stronger than Fujitora and well Whitebeard can punk Akainu easily. Only reason why Whitebeard didn't punk Akainu with ease during Marineford was due to Squardo stabbing him, having a heart attack mid battle and all the damage he took from the other Admirals and co. Keep in mind Whitebeard can bolster his own statics via Busoshoku and has Kenbunshoku to help him avoid her attacks.
Well,i don't think Rhon will one shot Shirohige easily IMO,even if Shirohige get hit by 20 tetraton nuke,he's still stand here,his durability is insane you know and this is oldbeard who still fight in old age with heart attack,magma in his stomach,his face get burned,etc etc,so probaly Shirohige will survive the Rhon attack.
Whitebeard for reasons above Artoria is not winning this he can dodge her attacks by the virtue of Observation Haki and when she is pushed to the limit her attacks are gonna be dodged more. By the fact her emotional state will get higher unable to deal with the Quakes Punches Whitebeard uses constantly destroying the battlefield eventually outlasting her, being above people that fight for atleast 10 days. Nothing Artoria is capable of as well as she can't use her barriers while using an attack so if she clashes head on with Whitebeard an easy 1 hit ko is in order.
But we don't know how the full power of gura gura no mi so far,if Shirohige want to unleash his quake power in full,there is the chance he can break the Rhon barrier,also i don't think the nasuverse mechanic is effective in other verse.
However,i agree with the Rhon spam,altough Shirohige can tank the first NP,i don't think he will survived in another shot,after the first attack he will fatally injured,but he can still fight,aside that yeah she just shot him once again before's too late.