Before making false accusations, you would do well to familiarize yourself with the definition of "plagiarism:"

plagiarism cannot exist when “(original) source/author unknown)” is CLEARLY STATED in all referenced posts. you're old enough that such basic logical facts should need no explanation.

You’ve crossed the line into slander and defamation here with claims that have no factual, lawful, or legal basis.

If you weren't hiding behind an anonymous account, this could be well-considered a trespass by way of slander, defamation, and harm in public forum - with claim pressed against you, as a man, for said trespass against i, a man, in a court of law, should the trespass continue and remedy not be provided.