This mod is no longer maintained in 1.21.9+, because Mojang fixed the /setworldspawn command to make it work in all dimensions in 1.21.9!

SpawnAnywhere

Set your world spawn/respawn location to anywhere.

Commands

• /spawnanywhere setspawn - Sets the initial (first join) spawn location
• /spawnanywhere setrespawn - Sets the respawn location if the player doesn't have any other (e.g. bed)

To execute these commands you need be an operator or have spawnanywhere.root, spawnanywhere.setspawn and spawnanywhere.setrespawn permission.