At least I haven't found one for Jekyll and 11ty, the two SSGs I have worked most with. It seems an architectural limitation of the SSG model.
All I want to do is to say "This blog post is ready to go on Jan 1, publish it without any action from me." Trivial in WP. People talk about cron, but really? I'm a dev, I can handle cron, but it seems a bit much to use to schedule a blog post.