"Fake news" isn't a metaphor, it's a thought-terminating cliché. It literally literally means the news is a sham, not genuine.
To your credit "to" in the headline here could be considered misleading. It implies "[If the proposal by Volodin, a close ally of Putin, is successful] Russia to punish ‘fake news’".
Silverfish's brow furrowed. "Well," he said, "yesterday you said—"
"I mean metaphorically," said Dibbler quickly.
"Oh. Well. Metaphorically? I suppose not—"
"There you are, then."
— Terry Pratchett