Homemade laundry soap? Don't laugh -- it's amazing stuff.
I have a variety of allergies and skin issues, too numerous to mention here. Suffice it to say that if it smells good, I can't be near it and if it it is washed in commercial laundry detergent, I can't wear it.
Pleasant by-products of making this at home: it costs about 85 percent less than the stuff from the store, it is gentle (and therefore doesn't eat away at clothes -- or skin) and I am not buying a bottled, diluted product that has been shipped from who knows where, with its environmental impact expanding by the mile. I am not an expert and I have no idea how much this reduces our laundry's carbon footprint. But it has to help.
The basic recipe is here. I use a vegetable-based, natural glycerin soap and I do not add essential oils, though I recommend doing so if you are not allergic.
Go forth and have clean clothes. Enjoy