zone 4 - ES will work, sun is not an issue, winter protection is needed - you should expect winter diebacks on the old woods, the blooms will come from the new woods...mulch the base heavily for winter protection..

Annabelle - most definitely reliable for zone 4 - blooms on new wood, hardy and tough, zone 4 should not be an issue...should expect some winter diebacks, you may even want to trim the bush down to about 18 inch to 2 ft every spring to encourage more new wood growth (and thus more blooms)..

ES is more a zone pusher for zone 4, annabelle should be a reliable performer.

other reliable performers for zone 4 are those bloom on new woods - limelight, quickfire, pinky winky...and they actually like to have more sun...but your 4-5 hr mid-day sun in wisconsin will do just fine.

nothing special about watering - just need well drain soil at the site - the weather is more moderate in zone 4 - just watch the plants during the continental heatwaves in july/aug...

jmho.