We never saw a B-Class connoseiur (Neither S-Class, cilan didnt even reached his goal). And in BW we only saw 3 connoseiurs: Cilan (A), Richard (A) and Burgundy (C) it was a very poor developed thing, we additionaly saw one in XY as a judge but we dont even know his class.
Unless...you mean BW080: Clash of Connoiseurs, which blurb is:
Joy that the Gym is closed! While they’re wondering what to do next, a limousine pulls up and a rather imposing man emerges, asking for Cilan. When Cilan introduces himself, he is quite forcefully “invited” to the home of a wealthy man named Mr. Hatterly—and Ash, Iris, and Cilan are all thrown into the limo to make the trip!
Mr. Hatterly has decided that it’s time for his young daughter Marigold to have her first Pokémon, and he’s enlisted the aid of two A-class Connoisseurs: Cilan and Ricard Nouveau. Mr. Hatterly wants them to pit their expertise against each other to decide which Pokémon is best for Marigold, and the Connoisseur competition begins...
...and is quickly crashed by Cilan’s rival Burgundy, who’s disguised herself as an S-class Connoisseur, the best of the best! But after “Fauxgundy” makes a bad guess about which Pokémon is Marigold’s favorite, Cilan and Ricard quickly unmask her and send her on her way.
Ricard thinks Petilil is the perfect match for the little girl, and her father agrees—but Cilan is convinced that Marigold has already bonded with one of the other Pokémon who live in her father’s garden, and he puts his sharp nose to work figuring out which one. Mr. Hatterly suggests they have a battle to settle their disagreement, and whoever wins gets to make the decision.
Cilan’s Crustle defeats Ricard’s Purrloin, and Cilan reveals his choice: with some help from Ash and Iris, he’s tracked down Marigold’s friend Foongus! She’s utterly delighted with the decision, and Cilan is declared the winner of the Connoisseur competition.
Mr. Hatterly’s butler recommends that our heroes head to Virbank City for Ash’s next Gym battle. Cilan excitedly seconds that suggestion, and they’re off!
So, theres no episode with the actual description you said (no tournament, no B-Class) but it feature cilan and richard competing since they were both called as connoiseurs, and burgundy disguising herself cause she want the job too. Hope it helps.
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