Remove Brush Wet Edges

I don't think you can.  But if it's not active why does it bother you?

If you are troubled by the apparent watercolour wash effect you get when you overlap brushstrokes this is a function of the Opacity setting.  You need to set Opacity to 100% to stop the overlapped stroke transparency.  The Wet Edges feature will not get rid of the transparent, wash look.  It adds the dried pigment edge look you get with transparent watercolour paint washes, where the sediment dries at the edge of the paint.  Wet Edges, and reduced Opacity, and a Spatter Brush tip make for a nice watercolour look.

David