Could you create an Issue on GitHub?
https://github.com/FilipePS/Traduzir-paginas-web/issues

Unfortunately DeepL does not support website translation.
I could even put the option, but the translations would be bad or break the layout of the site.
I have plans to release an extension that shows the translation by hovering over the text. In this case it would not translate the page, but it could support any translation mechanism.