Stevia could be a good option, but you will no doubt have to steep it in water. I haven’t done the research but you could probably find a good ratio online that would equal out to sugar. It might require a lot of leaves! Not sure what hardiness zone you are in but I’ve sold it for years in the greenhouse. I believe it is hardy to zone 7 but don’t quote me!Has anyone tried to back sweeten their wine with sweeteners other than sugar? What were the results. I was thinking of giving stevia a try.