You can treat it like a rock garden with alpines or even creeping sedums, or for a more medium height try upright sedums or dwarf asters or even hardy mums. Other types might be hostas, just match the size to your area. Shorter echinaceas might also work or rudbeckia goldstrum. True wildflowers can be real fussy; a little domestication often makes them easier and more permanent.

The OP did ask for Mn natives so some of the suggestions are not valid.

Go to the Prairie Moon website and order their catalog. In it, they list a large number of natives showing the height, color, sun, water, etc specs. In there you can find short natives that will be just right for you. I like polymonium reptans(Jacobs ladder) for early blooms. Also look for Silene , Phlox, Asters, Echinacea(Cheyenne Spirit) , Coreopsis, etal, among others.

Stay away from the droll Hostas and Daylilies.

You will have no trouble filling in that space with natives which will provide food for butterflies.

Do keep in mind that the area is commonly known as a "Hell Strip", hot and dry. So plan accordingly.

Hot and dry for a such a "hell strip" plant opuntia cactus, several are native to Minnesota. That "hell strip" is often planted with large trees often with heavy shade so then the cacti are out and you have a real problem. Virtually all shade and especially heavy shade plants do not like it dry. Also hot dry adapted plants very often have a midsummer period of dormancy. So not all of them will have a full season presence.

Please do be aware that native plants usually have very specific adaptations to where they originally came from. You must generally get seed and or nursery stock that originates very local to your location for success, and duplicate the original conditions carefully. Especially wild native seed generally needs to be local.

If you are willing to accept partially domesticated perennials, and are willing to make sure to water if necessary, for part shade there are low growing monardas and echinaceas. Or try Canada anenome.

Thanks for all the ideas and feedback, everyone! There's a newer maple (guessing 15-20 yo?) shading part of it throughout the morning so it's not totally boiling in the sun.