I believe you are asking for the statistical data of which ones are used at the greatest frequency, correct? I can do that.
Smogon submits a monthly report in literally every format available. I will list you the most recent results (November) for each tier at the most basic average trainer rating in Singles format, as it is the most common.
In Ubers, out of over 341,000 battles, Primal Groudon made the most appearances, appearing nearly twice out of every five teams (38.1%).
In OU, out of over 1.8 million battles (sweet Mother Mary), Therian Landorus was used the most, as more than 1 in 4 teams carried it (26.2%).
Down to UU we go, Scizor leads the way. In over 261,000 matches, Scizor showed up about as much as Therian Landorus in OU (26.8%).
Further down we go to RU, where in 102,000 fights, we have the least confident #1 Pokemon in all of the tiers mentioned, in terms of both overall usage and its statistical usage-stat lead over #2. Blastoise holds a 22.8% usage rate, while #2 Arcanine holds a 15.3% rate.
Nearing the bottom at NU, in 72,000 matches, Incineroar holds the top spot with dominance (29.2%).
And finally, of all the officials tiers of Pokemon according to Smogon, we have the nobodies in PU. (Which, let's face it, comprise like half the Pokedex. Or it feels like it, anyway.) Oddly, there were over 30,000 more matches of PU undertaken this past month than NU (a total of over 103,000), and the leaderboard here is like RU but even closer. Mesprit holds the lead with a usage rating of 20.5%, but Hitmonchan is close behind at 15.4%.
Additionally, if you want to look for non-standard metagames or other formats like doubles, you may see the entire index here. (Remember to select the correct month so you can be sure your stats are as up to date as possible.) I hope I was of help to you, and goodnight.
