Minecraft is written in Java, which is Unicode. That means that in theory, all characters are supported, from Spanish eñes to Chinese, to Arabic characters, to emojis. The only bottleneck, though, is the font that Minecraft uses for the chat, whose support for Unicode is far from complete, as seen here on
dafont. However, it does cover all accentuated vowels, both grave (à) and acute (á) as well as the German ß, the Spanish ñ, the Portuguese ã and the French œ.
Being Spanish myself, a restriction on accents forces me to write poor Spanish, which is something we should probably not stimulate, especially having young kids being a great part of our Cubecraft gaming community. For example, it forces me to write
Que haces? instead of ¿
Qué haces? or
tambien instead of
también. And although I am not German, I can imagine that it can be a pain to have to write
gros instead of
groß.
The developers should probably add an extra layer in between the bad words filter, which would normalize the text input to ASCII so that
trûmp would be
trump, after which it would be picked by the filter and not pass.