You might be able to achieve such an effect using shaders.
The biggest problem would be the wrap-around. You could 'detect' that projectiles and units are on the border of the map, then move them to another border corresponding to their velocity. This would require tracking all projectiles which is extremely performance heavy. For beam lasers you could just spawn another beam at the other map border. For explosions spawn another explosion at the other map border, etc. You would also need to override pathfinding, Spring's pathfinding isn't designed for this. That by itself would be a big project.
Additionally, I never tried this but it in theory could work, you may override some of the built-in Spring functions with your own. In particular,
Spring.GetUnitsInRectangle
Spring.GetUnitsInBox
Spring.GetUnitsInSphere
Spring.GetUnitsInCylinder
Spring.GetUnitNearestAlly
Spring.GetUnitNearestEnemy
Spring.GetProjectilesInRectangle
to account for the wrap-around.
This might smooth out some of the problems that could occur with the other gadgets and widgets.
The camera might be a problem.
You would also have to override unit aiming and targeting, basically everything...
