I have my doubts but you would be amazed by what can be done when a game gets tailored to a very specific hardware configuration (basically consoles).

Like you do see some versions of modern games making their way to Switch like The Witcher 3 and Apex Legends with very compromised graphics and performance. And the Switch version of Dark Souls Remastered was the only one that kept the original games models and textures unlike all other platforms.

But Valheim already compromises on graphics a lot, and there is typically a lot more calculations going on in these procedurally generated games which are more tricky to compromise on because they are fundamental to gameplay.
Take the way that the game handles 'instances' for example. I'm sure they would need to either optimise that to a fraction of the burden that it currently causes, or limit the players ability to perform large scale building/terraforming. Currently it can bring noticeable performance drops to even the more powerful rigs.