An option would be to reset your world to an "unexplored" state with a mod. This would let you preserve you homesteads and other locals that you want to save while wtill getting the new content.

I've used the UpgradeWorld mod to good effect. I'm still playing on my original world from 2 years ago but with the new content as it gets added. Also helps clean up the mine pits from all teh copper and Silver I farmed working up the tech tree.
https://valheim.thunderstore.io/package/JereKuusela/Upgrade_World/

Just be sure to back up your world before using. I've never had a problem but better safe than sorry.

Good luck