Maybe it could be named after the
Nemetes tribe to give a name like Nemets, which would fit in nicely with the Slavic names for Germany (e.g. Niemcy in Polish).
Cheers,
Nigel.
My understanding is that the etymology of Niemcy in Polish and its equivalents in most Slavic languages is that it comes from a root word meaning "mute," which evolved to mean "foreigner," and then "German," specifically, as the Germans were the closest and largest neighboring culture that didn't speak a Slavic language. You can imagine an ancient German-speaker arriving at a village or marketplace in Slavic-speaking territory and not being able to communicate. Interestingly, in Arabic, Farsi, and historically in Turkish, the Slavic root word for Germany was adopted for the local name of Austria - an-Nimsā is the name of Austria in Arabic, for example.
Aside from the afforementioned roots (from Germania,the Tuetons, the Allemans, the Saxons, and Slavic "mute"), another possibility is to derive the name from Prussia - The only case of this in modern language is Tahitian, which calls Germany by the name "Purutia".
Another name from Old Norse called Germany by the name "Suðrvegr," which means "South Way" as an equivalent to Norway. Perhaps Vikings in early England could spread this etymology, thus making "Sudway" as common name for Germany in English.