Is there a way to stop the theme and especially plugins listed?

Is there a way to stop the theme and especially plugins listed?

No, very doubtful that you can ever pull that off unless the site maintainers will honor requests not to list particular themes or plugins.

What you are asking is the equivalent of “Is there any way to disguise the make and model of a car?” Not really. You’d have to replace pretty much everything. I can look at site and tell you the same information in 30-60 seconds. The information is all pretty much in the source of the page. To prevent sites like that, or people like me :), from fingerprinting your site you would have to jump through many, many enormous hoops of flaming acid, and would probably take a rebuild of significant parts of the WordPress Core.

I suppose you could blacklist requests from that domain but that may be a server level task depending on how the site works.