The council has no ability to punish anybody. Its members are sovereign entities, and so they could punish individuals, or themselves, or each other, to some extent, but they likely won't.

Even more so than the UN, the Council of Europe is ultimately just a meeting between sovereign entities, it exists at their whim. Collectively the members would prefer to, at least on paper, adhere to certain rules which might prove inconvenient in practice. For example, on paper as a CoE member Russia did not have Capital Punishment or Torture. In principle Russians who annoyed Vladimir Putin could perhaps be imprisoned but not tortured or executed. In practice of course the Russian state continued to kill people, indeed including poisoning people in other countries, but it did so illegally. In March the Council kicked out Russia because invading another member country on a flimsy pretext was taking the piss.