As long as the mesh is smaller that the butterfly it will be OK. I would avoid too fine a mesh because of the shading as you said.

Enviromesh netting is fine. Very little shading. 90% of light passes through.

Is that the same as debris netting?

No idea what debris netting is.
I only use environmesh, or similar. Hence my advice on that product as being suitable.

Having just googled debris netting, no way I'd use that stuff.

Thanks