GrapheneOS
The provided keyboard in GrapheneOS is just crazy if you need more languages, especially if you have also voice input keyboards like SayBoard.
All this keyboards are switched after each other mixed up normal keyboards with voice keyboards (which was not the case in earlier versions), then also very often in unexpected sequence. This is just crazy.
A good keyboard should have a possibility to select, let's say 2 active languages for easy toggling, and another languages with extra toggling. A good keyboard should let you to group keyboards as you want, etc. etc.
I have always a pain if I need to use a multiple language input in GrapheneOS, which is a normal use case by many Europeans and young people.