When it comes to the comparison between Exxon Mobil Corporation (NYSE:XOM) and Shell plc (SHEL), there is a clear winner. Exxon stands out with larger margins, superior EBITDA, free cash flow, and profits. Not only does Exxon have a $50 billion buyback plan in place, but Shell's $4 billion plan pales in comparison.

Financial metrics play a crucial role, and Exxon outperforms Shell consistently. With a higher gross margin of 35% compared to Shell's 26%, Exxon showcases its strength. This margin difference has been evident for years, highlighting Exxon's ability to generate higher returns. Additionally, Exxon leads in EBITDA and free cash flow by $16 billion and $15 billion respectively.

Analyst ratings are also in favor of Exxon, with more buy recommendations and a higher percentage of strong buy ratings. Although both companies receive hold ratings from quants, Exxon has had a history of strong buy recommendations in the past year.

Exxon's commitment to returning excess cash to shareholders is evident with its $50 billion share buyback plan, representing a substantial portion of Exxon shares. In contrast, Shell's $4 billion plan seems insignificant in comparison.

In terms of dividends, Exxon has consistently increased its dividend for 20 years, while Shell has a shorter dividend history. Exxon's commitment to dividend growth gives it an advantage in this aspect as well.

Considering all these factors, it's clear that Exxon emerges as the stronger investment opportunity. With its superior financial metrics, commitment to cost-cutting, and share count reduction, Exxon proves to be a buy. On the other hand, Shell's lower price may be justified given the numbers presented.

In the Exxon vs. Shell battle, Exxon takes the crown as the clear winner, making it an attractive choice for investors.