Arborescens or "Anabelle" type hydrangeas would work best for you. Fully hardy in zone 5, very shade tolerant and heavy bloomers. Should reach 5' in a season or two but not much beyond that.

i did some research, it seems there is an ”updated” version called Incredibal. Think this will work?

IME, 3-4 ft is more realistic than 5. They often die back during the winter, but since they bloom on new wood, it doesn't affect the flowering.

I have an old fashioned deutzia that might work.

Think Incrediball hydrangea would work?

What is the consensus for Quick Fire Fab hydrangea for this area? I love the color of these. Would make a beautiful hedge!

They probably want more sun than they'll get there.

Panicle hydrangeas require a LOT of sun to bloom well and color up properly. Doubt these would work well in your situation.