I can't think of any hardy grasses which approach the appearance of Purple Fountain Grass. There are red Panicums and bronze Carexes, but they are nothing like PFG.

If you like the size and color of purple fountain, try Miscanthus sinensis purparescens

Panicums aren't very showy until fall, and in my opinion don't make the best looking container plants.

Any of the Carex, specifically the bronzes and amazon mist, but they have different growth forms and don't get as big as fountains.

If I were you I would look at 'Red Baron' Japanese Blood Grass or Cogongrass (Imperata cylindrica). It is hardy in your zone and is beautiful in containers.

I moved my Blue Lyme grass (Elymus arenarius) to a large container on the deck because it was too invasive in the garden. The steel blue color is a nice contrast to the other plants. It seems to do fine, and I just give it a complete haircut every spring. For some reason I hardly ever get plumes, though.

Larry