It's possible, but if it's worth it depends on how much time you want to spend messing with it. For example, you could adapt a compound feed drill press vise into a compound feed tool holder. If your wood lathe is "big iron" with good bearings, you could work to reasonable precision. Single point threading will still be out of the question unless you rig up a power feed with gearing, and at that point it's way simpler to just buy a proper metal lathe.
But...if all you want to turn is brass or aluminium for an occasional flashlight body, use your lathe as is. Use sharp gouges and scrapers and take small cuts. The hardest part for me is getting a straight cylinder, a file helps here.
Buy a die and holder for the threading. If you can chuck your workpiece and support the face of the die on the tailstock while starting the cut it will help keep the threads straight. Don't use a tap in a chuck in the tailstock unless you allow a way for the tap to thread in at the proper pitch.
I use a plier type knurling tool and although I can't slide it along the workpiece without the compound feed, I can make overlaping narrow bands of knurling if I am carefull.
This works OK for little "one-offs" like the switch guard ring I made for my A2 recently. It took two tries and about an hour, but it's not something I could find for sale anyway so...