They were. I played the Y6 demo at Gamescom once.
Yeah, they were there for the international audience and maybe there were english interviews.
Even Fist of the North Star had a booth there but thats not what i'm talking about.
I'm talking about game presentations in the official german streams
where they invite devs and or showcase new games.
Its a german event, so theres always one official german stream
and also german press is there to report about the event.
Yakuza games were never part of the streams.
For example, if you take a look at the biggest german videogame website 'Gamestar'
they didnt even mention any of the old RGG stuff once in their Gamescom reports.
The first time they mentioned Yakuza 6 at all, was when Sega leaked the full version on PS4.
Lost Judgment will be a part of the official german Gamestar Gamescom stream.