If I had to hazard a guess I’d maybe say Usain Bolt or Lebron James. Lebron is super popular but basketball in a couple select parts of the world is very niche. What I’ve figured out over the years tho is that at least from my experience. Is that Messi is more of a household name than Ronaldo. I live in the states and my girlfriend didn’t grow up playing or watching Football at all. And I told her the name Messi and she knew who that was but she wasn’t sure if she had heard of Ronaldo. Same with a lot other people I’ve asked the question. I’ve either always gotten that they know Messi and Ronaldo or just Messi. Never just Ronaldo. I just find it interesting since Ronaldo has way more brand power.