Cigurd having looked into Japanese keyboards matching your requirements it is indeed highly likely that GBoard is requiring a connection to the cloud to determine your kanji/katakana alternatives.

The only thing I can suggest is to try leaving GBoard with network without inputting anything, adding the language packs of your choice and leaving it with internet for 5-10 minutes depending on connection speed. Once done, disable network and try to type as you would and let me know if the kanji/katakana appears as it should.

I can also confirm with what @Hulk has reiterated nobody has altered or censored anything you have previously posted, Everything still reads as per your quote.

      2 years later

      MetropleX By the way, yes, turning on Network connectivity downloaded the library, and after turning it off again, the Gboard still works as it should. Thanks.

        with the topic already on gboard and other alternative keyboards, will the swipe typing work on gboard correctly without network permission?

          0j923jd023j It works fine both in English and in French. But FUTO keyboard, although far from perfect, is also doing a good job en English and a decent job in French.

            Eirikr70 Spanish is my main and you can use standard version, that doesn't support swype or the one that includes support for the Google Swype library

              MetropleX if you remove the 'Network' permission you don't need to worry about the "tracker

              MetropleX likely already knows this by now, but because this is 2 years later and it wasn't mentioned in this thread, for the sake of anyone else who ends up here: don't trust that turning off Network permission would prevent trackers from phoning home. Installed apps can communicate with each other if they are designed to do so, and could just share the tracking data to another app which does have Network permission (in Gboard's case, it would be reasonable to assume that it could communicate with Play Services or Play Store for instance, and you likely needed to keep Network permissions enabled for at least one of them.)

              That being said, it's generally believed that Gboard respects the user's choice of opting out of data analytics, but this could change at any time. If your threat model requires it, you may not want to use Gboard until App Communication Scopes is ready. It will allow you to restrict inter-process communication for any app which should prevent Gboard from being able to leak data.

                check out HeliBoard on Fdroid! it's amazing! it seems to have everything