Grey water design using worms? And winter friendly?

I am in TN and need to take some of the work load off of my failing septic (traditional) I figured recycling the grey water from my washer and kitchen sink and showered would be best? I get freezes so I thought one of the worm filters would probably be best. Can anyone tell me where to find design plans? Does anyone have one? Comments? Pros ? cons?

What about alternatives for black water?   I'm considering doing something different all together for my toilets and retiring the septic completely... Can anyone point me in some good directions for ideas and possible DIY designs? They must be low cost and simple enough to not need a doctrine to install .. lol.

Thanks for your time and assistance 🌷

Where are you Evelyne, if you identify your location you may be lucky and have someone nera with experience.
Worm systems are well established in the marketplace. Have you researched anywhere?