Here they are :
Chrome - https://chromewebstore.google.com/detail/zwiftpower-zrs/pndlnaffagkomheigejpimbpdmapmfef?pli=1
Firefox - ZwiftPower ZRS – Get this Extension for 🦊 Firefox (en-US)
I havent made these, but someone made it possible what Zwift is lacking since July while we kept on asking for it. ZRS scores on ZP.