Perverbial vs Proverbial

Proverbial is the correct word.

1. [only before noun] used to show that you are referring to a particular proverb or well-known phrase

• Let’s not count our proverbial chickens.
• The idea has acquired a proverbial currency.

2. [not usually before noun] well known and talked about by a lot of people

• Their hospitality is proverbial.
• His mastery of the French language was proverbial.

While perverbial is not a word.