Hello! Human engineer here and all of my shields have clipping issues, but I feel like there’s a very simple fix for this problem.
Simply make the shield out of combat position on the characters arm instead of on their back. I feel like this would solve every clipping issue for shields for all races, as well as help to set Guild Wars 2 apart from World of Warcraft which also places shields on the characters back when put away. You can see a few guards around Lions Arch with their shields this way— though they do have their weapons out as well. Anyway, just a thought. Thanks for reading.