In retrospect, "FIFA 17" seems like an obvious choice if you're guessing what would be tops in the most countries. "FIFA 17" topped the list in 15 countries, more than any other game. Many of the countries in this group -- Ireland, Costa Rica, Ghana, Italy, the U.K., among others -- are serious soccer nations.
Among other games ranking well were "Overwatch," which was the top game in seven countries. Those countries were predominantly in southeastern Asia, where eSports are incredibly popular. (Though, that can increasingly be said about many countries.) Surprisingly, "League of Legends," a free game that might have seemed likely to be more present on the list, was only the top game in nine nations.
In the US, despite middling reviews, "Call of Duty: Infinite Warfare" was tops.