In the vision, Pennywise appeared as a meteor that crashed and fed on the Native Americans in the area, taking many forms until settling on a clown.

Source: https://www.cbr.com/it-pennywise-benefited-ambiguous-origin/

It feels like some shit Pennywise might conjure up to extract that sweet, delicious fear out of those Derry kids.

Source: https://collider.com/cartoon-all-stars-to-the-rescue-drug-psa/

Pennywise, on the other hand, is immediately recognizable as an evil threat, no matter what form he takes.

Source: https://collider.com/welcome-to-derry-it-series-cast-plot-release/

"She reminds me of Pennywise and Dracula and Nosferatu.

Source: https://collider.com/the-nun-2-valak-director-comments/

The personality she brings to The Nun is reminiscent of Robert Englund as Freddy Krueger or Bill Skarsgård as Pennywise the Clown, and she does so without any clever one-liners or sweeping monologues.

Source: https://www.slashfilm.com/1382908/nun-2-bonnie-aarons-next-great-horror-movie-monster-actor/