I downloaded valheim on my Xbox to test things out ahead of finally bringing my buddies into the game. I hosted my world on PC and logged my Xbox character into the world as well.
I don’t know if it’s from the latest patch, or if it’s due to something with the Xbox version but the terrain decided to alter itself. The terrain dropped a few feet / hilly terrain changed shape leading to the loss of two of my three main structures due to them now floating. The trees and rocks floated too before settling into the new terrain shape.
I had a Black Forest mini island I used as a portal hub that decided to recede underwater, and a meadows base where the hills dropped significantly lower around a creek. My mountain base did not change at all. This world is post mistlands update as well, as I know that did affect an older worlds geography at the time.
Just a warning to those who may want to load up an established world to play cross platform with friends. I didn’t lose anything too significant that can’t easily be rebuilt. You may just want to start a fresh world for cross platform play.
Source: https://www.reddit.com/r/valheim/comments/11rkq26/crossplatform_warning/