This hadith has got no source and is interrupted in its chain of narrators.

Tabarani and Daylami have narrated this hadith in their musnad and in the chain, the narrator Jawaybir is extremely weak and Dahhak has not heard from Ibn Abbas. (Al-Maqsid al-Hasana p 26)

Zarkashi in his al-La’li al-Manthura fi al-Ahadith al-Mashhura writes that Nasr al-Din al-Maqdasi has narrated the hadith in his book Al-Hujjah reaching up to Nabi ﷺ, but Zarkashi did not provide a chain for it. (Al-Maqsid al-Hasana p 26)

Zaynudin al-Iraqi writes that Adam ibn Abi Iyas narrates without the exact wording the narration which al-‘Iraqi classifies as a weak mursal. (Al-Maqasid al-Hasana p 26). Imam Bayhaqi also narrates with the similar wording in his Risala al-Ash’ariya, but without a chain. (Al-Maqasid al-Hasana p 26)

In his book Al-Jami` Al-Saghir, Al-Suyuti could not identify a narrator reporting this Hadith with Isnad (a chain of narrations). Al-Munawy albeit writing an extensive commentary on it in, did not mention its origin. See al-Asraar al-Marfoo’ah, 506; Tanzeeh al-Sharee’ah, 2/402; al-Silsilah al-Da’eefah, 11 for more details.

So as a hadith it cannot be quoted. However, it can be quoted as a statement since the meaning is alright, as attested by the rightly guided Caliph Umar ibn Abdul Aziz (RA) who once said :

“It does not please me if the Companions of the Messenger of Allah ﷺ did not disagree [on a particular issue], since if they all agreed on a matter and then a person did not act accordingly, he would be astray. Yet if they differed on a matter, and one person took the opinion of one [of the Companions] and someone else took the opinion of another [Companion], there would be leeway in the matter.”

A scholar once authored a work in difference of opinion, to which Imam Ahmed ibn Hanbal (RA) responded, “Do not call it ‘The Book on Disagreement’, but rather call it ‘The Book of the Sunna.’” This theme was explicitly articulated by many eminent and orthodox imams, both early and late, such as Imams Abu Hanifa, Malik, Khattabi, Nawawi, Ibn Qudama, Ibn Taymiyya, Shatibi and many, many others. Fiqh doesn’t cause disputes. It’s the people with corrupted hearts and narrow minds which fuel disputes. May Allah have Mercy on all our scholars.

And Allah Ta’ala Knows best

https://mawdu.wordpress.com/2013/10/24/difference-in-the-ummah-is-a-mercy-but-not-a-hadith/
https://islamqa.info/en/answers/13623/is-the-hadeeth-differences-of-opinion-among-my-ummah-is-a-mercy-saheeh
https://www.askimam.org/public/question_detail/16588