@jan-1 , unfortunately I don't have a great suggestion for you. It looks like @robotdan is taking a look at the issue you created. I will follow the issue and check back in, once they update it.
Please feel free to upvote them, as that helps direct our development efforts. If these issues don't cover what you're looking to do, please do file a feature request with use case specifics.
As far as I know it is not possible, I believe Google builds that text based upon the redirect_uri. I would assume you'd only see the fusionauth.io domain listed if you're using our hosted URL. If you are using an enterprise plan with a custom domain (login.example.com) you shouldn't see fusionauth.io mentioned.
I know in the Google cloud console where you configure your credentials there is a customization option for the consent screen, but I do not know if that will modify this account chooser or not.