Look in your area for a shop that does ready-to-wear clothing alterations. Sometimes dry cleaners will offer those services. Altering a dress shirt to fit you better is a relatively inexpensive service and then you don’t have to worry about this anymore. As a 6’ tall woman, this is literally one of the reasons I learned to sew.
I’m gonna go ahead and assume the question was asked in good faith and answer it the same way.
If your washing machine is working, there should be no fecal matter left on the clothes after washing. However, many clothes lose color over time due to a number of factors, one being the dye slowly bleeding into wash water each time you do laundry. Many black dyes start to look orange or brownish as they fade, and two socks won’t necessarily fade at the same rate. The only way to put the color back is to redye them, which might not work depending on what the sock is made out of.
I wouldn’t worry about poop, these are clean, just faded . However, if you want to have 2 black socks, you’re gonna have to buy a new pair.