I would investigate the use of comfrey as a border plant that might at least contain the nettles.
Sunchokes might work. You might try seeding the area at the beginning/end of the season with something that establishes quickly, like buckwheat, which is edible, useful as a green manure, and hosts nitrogen-fixing bacteria. It might outcompete the nettles and allow slower-growing species a chance, after you come and chop-and-drop the buckwheat.
You could just try to manage the nettles mechanically. Harvest them and make silage, if you have livestock, or submerse the cuttings in a drum of water, preferably oxygenated, to make a good liquid fertilizer. I don't properly remember, and I can't find the link to the source material (it was another
thread on this site with links to other material), but I seem to recall nettle water being a decent flowering/fruiting stage fertilizer, with comfrey water being its vegetative state corollary.
If you have any issues, I suggest you develop a taste for nettles, or for goat and goat
milk pastured on nettles. Good luck, and keep us posted.
-CK
A human being should be able to change a diaper, plan an invasion, butcher a hog, conn a ship, design a building, write a sonnet, balance accounts, build a wall, set a bone, comfort the dying, take orders, give orders, cooperate, act alone, solve equations, analyze a new problem, pitch manure, program a computer, cook a tasty meal, fight efficiently, die gallantly. Specialization is for insects.
-Robert A. Heinlein