They'll be fine, just make sure they're kind of staggered and not side-by-side. Also bear in mind that ES are full sized bigleaf hydrangeas, so you could plant a smaller variety in front of them, also staggered.

where I live I do: Arborescens or mid/full paniculatas in rear, full size bigleaf middle or rear, compact/semi-compact/dwarf bigleaf hydrangea in front.

PS: that newer section of fence looks awfully bare!

I like your idea about different hydrangeas, i may end up doing that somewhere else in the other garden. For here i think it may look better with just the three against the wall and something else in front. I just don't know what else to fill in this mulched area.

What are some dwarf style hydrangeas varieties? In my front garden I have three ES Originals and love the idea of mixing and could put two dwarf style staggered in between them. I would love the Blushing Bride or some other white, but I think the Blushing Bride is bigger than the Original. Any other white dwarfs ? What about Wedding Gown, any thoughts on that variety? I would really want a mophead white but the Wedding Gown looks perfect size to go in front and I can't find any dwarf mopheads.

And haha yea that new fence does look bare! I have a plan for that now too, just waiting on fall temps so i can drain my bank account on new plants and get that area looking good.

ES Blushing Bride is a tad shorter than Original, but not by much.

I have an Everlasting Pearl that I like, but apparently it's been cancelled in retail.

Wedding Gown is a solid go-to. It can get somewhat wide but mine hasn't gotten taller than 3'.

An alternate would be F&E White Out, but the blooms need as much shade as possible.