Chromium-Freeworld is the stock Chromium browser, just ‘built with all freeworld codecs and VA-API support’.
chromium-browser-privacy is a de-googled version of chromium, and aims to strip out all google integration but retain the chromium user experience. (Think chromium-browser-privacy is to Chromium, as GNU IceCat is to Firefox)
Most packages will have a short description available if you run dnf info %package%.