Personally I could only imagine expository/imaginative and persuasive/imaginative being done. However, I've had people class their work as expository/persuasive before, although I can't see how that's possible as the two purposes of those pieces contradict each other and what you end up with is a piece which doesn't seem to effectively persuade, nor does it effectively explore the idea as you're holding bias throughout it. Whilst I'm sure someone who writes well could do it, I just don't see the point really since yeh, they're conflicting purposes to base your writing around. Some examples are;
Expository/imaginativeExpository/persuasiveAs for persuasive/imaginative, many pieces which are classed purely as imaginative could probably be classed partly as persuasive too as they should either be making a point in their story.