Sorry to report there is no way around the lockout even using devcommands.

The spawn shrine is a sold NO-BUILD zone in an aprox 40 meter radius , but right outside that you can build any thing you want.

You wouldn't really want to when you think about it, the spawn point is one thing that is guaranteed to change as the game updates and new Forsaken zone bosses are added. The build lockout is so alter stones can be added without having to hose your entire world build so I'd suggest just accepting the limitation and think how to build around the spawn point. Maybe make it a "park" in your compound or such.

A trick I use to find the exact edge is to drop some workbenchs around the boundry and then try to place a wood post inside the zone, then move it outwards until I can place it. repeat all the way round. you can buil a fence, wall, dig a trench, etc right up to the edge of that area.

Also, the lockout is a cylinder, you can't build up and then over or dig under. I've tried.

I should add I have not looked to see if there are mods to get around it. So if you really want to do something it might be worth your time to check Nexus mods and Thunder Store.