Well they have very different requirements. The oakleafs going to like more shade and not tolerate full sun very well. The Limelight should do fine in full sun.

They're also have two totally different growth habits, the oakleaf can be sort of wide and spreading, but the Limelight is going to be more upright like a crepe myrtle tree (you could always plant something under/around it.

Keep in mind too as far as a hedge both of these are deciduous, and you'll have to leave the winter branches up to keep the buds in place for the next year (Does Limelight bloom on new wood?)

But that's a long distance for any one hedge, maybe breaking it up in groupings back and forth. Maybe throwing in some other hydrangeas in for color.

Limelight blooms on new wood and will be very hardy and fast growing in full sun in zone 5. Oakleafs bloom on old wood, slower growing than limelight, and can suffer some winter die back in zone 5.

I agree with Creech in that 80 - 90 ft is a long row of any one thing. Maybe some trees in between the Snowqueen to form an alley?...Maybe mix in some evergreens to hide the bare stems during winter....whatever, just mix it up a little....yg