If you want to do the job properly you have to remove the hub.
If you want to do a quick job, you can cut the brace out and feed it past the hub. I had to do this when I was the Guinea pig for S3 rears, and found that S3 Splash guards don't fit, hence the tweaking that all do now.
The pic shows the brace removed from the standard GTi/Ed30 Splash guard.
Pic with the guard fitted showing the removed brace (runs between the grey painted edges and is about 1" wide).