could you specify what you would prefer in a plant?

height, color, butterfly friendly ...

and do you know what kind of soil you have, sandy or more heavy/ loam-ish?

there is probably no exact substitute, so more info would help

Clay soil that is dry

Yarrow looks nice for a substitute might use that!

Go for one of the (Yarrow) -Achillea filipendulina. They are taller and perform better than A. millefolium.

tall, tough & fall blooming = vernonia novaborecensis

I would like a smaller one, plus my grandmother has been growing yarrow for years and it always performs amazing

What do you mean by in the mailbox? As in a around a mailbox? Or something else?

If you're following a plan, you need to replace a tall plant (joe pye weed) with another tall plant, no?

tall, tough & fall blooming = vernonia novaborecensis

It was my understanding that the growing conditions for this plant were quite similar to that of Joe Pyeweed ie both like moist soil.

It's nicknamed ironweed for a reason ;) It can grow in a swamp for sure and it also does fine in drier conditions. Northern Virginia has very wet years and very dry years ( like 2023) so I appreciate plants that can do it all. I've been using vernonia Iron Butterfly quite a bit.

V 'Iron Butterfly' looks totally different from V. novaborecensis. IB looks like a 2 ft tall spreading shrub--not tall, not narrow and upright. A great plant, however.

A mature Iron Butterfly is 3x3 for me while v. novaboracensis is tall & narrow, like 6x2. I thought the OP needed a tall plant to replace JPW in a planting diagram. If Iron Butterfly is allowed to set seed, the offspring are tall & narrow. Both are great plants & pollinators love 'em.

There does not seem to be enough threads about Ironweed. It appears to be native throughout a large swath of North America? What say you @Jay 6a Chicago?

I have ironweed - Vernonia novaboracensis. It is indeed quite tall. IDK if it will do well in dry soil, I think that might be pushing its tolerance.

I grow Vernonia crinita 'Mammuth' and on dry years the length of flowering time is greatly reduced.