Bangiras has translated the preview summary for DP75: Enter Contest Master Wallace!, which will air on April 17th in Japan. This episode features Wallace’s first animé appearance, since the animé followed Pokemon Emerald’s storyline rather than Ruby and Sapphire’s when it came time to battling the 8th Gym Leader. (In Ruby and Sapphire, Wallace was the 8th Gym Leader, but was promoted to Elite Four Champion in Emerald, with Juan taking his place as the 8th Gym Leader).
When Ash and friends take a break at a Pokemon Center, they see information about the Valor Lakefront Pokemon Contest: Wallace Cup on a monitor in the lobby. Wallace, who has been working fixedly to establish himself as a Contest Master, is rumored to be holding Pokemon Contests in the Sinnoh Region. Dawn, having lost her self confidence, decides to enter the Wallace Cup as a comeback battle.
Following this episode is DP76: Seven Stars Restaurant! A Full Course in Tag Battles!, which will feature the return of May (most likely only for a few episodes, not permanently). We posted the summary for that episode a week or two ago, but it was lost with the data that was deleted.