When I need to soak some things outside of the washing machine, I just use a mop bucket. Lately that soaking has been whites in oxyclean to get them looking more white again. Oxyclean (or any similar non-brand name oxygen based agent) is great for organic stains (blood, sweat, oils, grease, food) and smells, but bad for wool. DO NOT USE OXYCLEAN ON WOOL. For my wool stuff I just use regular detergent in cold water and hang dry. If you’re trying to get smells out of wool you might try drying them in the sun. Wool also doesn’t do great in hot water, but that’s okay. Just trade heat for time, i.e. letting something soak in cold water instead of a short wash in hot water. Same principal used to make cold brew coffee.

If there is a filter to be cleaned on a public machine, you can probably check it before running your own through. At the very least give the machine a sniff first. Sometimes a quick rinse cycle with an empty machine is all that’s needed to clear out the lingering funk from the last load. If not, the machine needs maintenance.

Laundry advice is weird in that it can be very broadly applied and general (the actual chemistry and fabrics are pretty similar everywhere), but also hyper local. What works in one region might not it another because the water is different, chemicals have different and confusing names, etc. The best advice is really to read the clothing tags (and learn to interpret those laundry hyroglyphs), read/research the detergent ingredients and instructions, group like items together, and test new tips and tricks on less critical pieces of wardrobe before doing an entire load.