I grew up on the zone 7/8 interface in east AL... spent most of my first 27 years roaming the woods... never knowingly saw a hazel/filbert... but they're present here on my farm in KY. Shrubby bushes to about 8-10 ft. Hybrids with some of the tree hazels might fit your specs... but I don't know how they'll fare in the heat/humidity... though it gets pretty hot & muggy up here...

The folks at KY State U. are doing some work evaluating EFB-resistant cultivars here... KNGA - KYSU hazel trial

Daughter of Cecil Farris, the 'dean' of MI hazel growers/breeders, was living in Franklin TN a number of years back, and had some of Cecil's EFB-resistant selections growing at her place... IIRC, G-22 was the best... don't know if any of Farris' selections are now available... Grinnell Nursery was handling them; don't know if they're still in operation.

I'm in Atlanta and have several hazelnut planted in 2009. We've had two years of crops. I bought mine from burnt ridge nursery in the northwest. My largest is Lewis and it is about 25 ft. They are great screening trees. They are wind pollinated and have specific cross pollination requirements. They are being bred 'blight' resistant, which apparently was /is a big concern. I may be zone pushing, but they seem to be doing fine. Blight is ok but the squirrels are hell.

I tried one year in zone 8b, in Florida, from 3x bare root plants, and they didn't ever come out of dormancy, just died and rotted.

I'm in 7A and they are doing fine. The main problem is squirrels, they will eat every nut. Make sure to look for blight-immune cultivars. Raintree sells the best ones. I am growing Yamhill, Jefferson, Santiam, Theta.