As far as I can tell, the Dev is no longer interested in making any new updates or new versions of FlowScape. You might as well look for another similar game such as: CINE Game World, Menyr, Everywhere, or World Maker. However, I don't recommend World Maker as it's very limited and the publisher explicitly said that you can't use any of its imagery for your own projects, youtube channel or business.

Thank you for your advice. I didn't know that the dev has stopped working on Flowscape 2 and just looked for your mentioned other games. But when entering Cine Game World and Everywhere on the Steam start page, they didn't show up. Only Menyr did but this is not for me, there are obviously ingame purchases and I don't do that, also I'm only a single player and the game itself looks completely different than Flowscape. And World Maker, I came across it a longer while ago but it's still in my wishlist and has been there for over a year by now.
So thank you for your thoughts and suggestions nevertheless. :-)

Steam doesn't allow AI content generated games. CINE Game World utilizes AI technology to generate voice acting for NPCs so that's why it doesn't qualify to be on Steam. As for Everywhere, they have their own game distribution channels.