They are almost completely identical.
As NX Gamer says in his video, Assassin’s Creed Valhalla runs on PS5 and Xbox Series X with a target of 60 FPS, and both consoles do a good job of this, showing only occasional minor drawdowns.
The Series X uses adaptive vertical sync, which causes frame tearing – not available with VRR, but not all displays support it. The PS5, meanwhile, uses full V-sync with almost no tearing, but occasional frame drops occur.
At the same time, both versions work in dynamic 4K. The blogger noticed that on Series X it sometimes drops to 1440p, and on PS5 – only to 1620p. However, due to upscaling, the dips in resolution are not striking – especially considering that both consoles rarely hold native 4K.
In cut-scenes, the FPS is on average 1-2% better in the Series X, but this difference with the PS5 can hardly be noticed by eye. At the same time, the PS5 is about 12% faster in downloads, which equates to about one second.
Digital Foundry is also going to release a detailed analysis of Assassin’s Creed Valhalla on both consoles, but when it comes out is still unknown.