Does the elemental boost from elemental wands/staffs still work?

They are all skewed and they are reduced.

They were removed in Big Bang, but then were added back with reduced bonus (10%/5% instead of the original 25%/10%). Unfortunately they screwed up the elements on each wand and staff. There is a chart elsewhere on this site that lists them each.

I was already aware of the changes up to the point you mention. I just heard on basil that they don't work at all anymore.