Blur Effect in XML/LUA

[Anumaril]

Riding off the back of my previous help thread, the last thing I'm interested in doing in my addon is creating a blur effect around the edges of the screen, almost identical to this video where it's done in Skyrim: https://www.youtube.com/watch?v=GlTeTdFAaaU (skip to timestamp 0:23 when Boethiah speaks to the player)

I've poked around various documentations for XML and haven't found anything at all relating to blur effects, much less targeted blur effects that leave a clear circle in the centre of the screen. Does anyone know for certain if this is (not) possible?

Thanks again! You guys are great