Can't figure out how to install OKBoard on Xperia 10ii

I can install the package and start/stop OKBoard through the cover action, but that doesn’t change much apart from it’s not possible to swipe between the preinstalled and activated native keyboards (in my case, english, german and emoji). Changing keyboards by pressing space long remains possible. No OKBoard in sight, though.

It’s not a separate keyboard to choose from, it works on top of your keyboard. Just start swiping after it’s installed.

Well what can i say. It didn’t work instantly, but now, after switching on/ off and changing some settings it suddenly works. No idea why. But, thanks, I’m happy now:)
Edit: turns out I’m probably missing a German dictionary. Works fine for text input though:)

The dictionaries need to be installed separately, with packages from different creators than eber42. For German you can choose:

Unfortunately, the German layout doesn’t seem to work on 64bit.
Austrian German works, but unfortunately it doesn’t insert spaces automatically, so it’s not really a fluent experience:(

Yes, but other languages have the same “feature”. Would the space be inserted you’d have no possibility to directly chose a different word instead of the inserted one.

But it’s working in English?

Ah, you mean the (not) automatically inserted space after entering the following word. Yeah, that feature is unique to English. (I haven’t tested all languages, but multiple non-English languages are affected)
You’ll get used to inserting the space yourself, just a matter of habit.