If you are on the lookout for a tool like Buzzsumo, I highly recommend you to check out Social Animal(socialanimal dot com).
Social Animal is a state-of-the-art content research product.
Utilizing natural language processing and machine learning techniques, it peers into what makes good content tick.
With Social Animal you can
> See top shared articles, compare top performing articles, analyze article titles and get article shares across all social networks.
> Find optimal title length, content length, day to publish and 6-month content performance history for any keyword or domain.
> Find real social media influencers, authors and see articles shared by influencers.
> Analyse performance of blog posts across social media, get sentiment analysis data and gain social media insights of competitors.