There is iocaine and nepenthes. You can easily deploy on your server. Given the scraper uses the correct User-Agent... which they probably do not do especially if everyone started deployed tarpits.
Would be fun if lemmy or piefed had an option to have the content of posts poisend as there are some new Crawlers crawling in the fedispace recently.
Or we could of course invent our own lemmy speech that is still english, but really weird.