Applin was a fun concept of a Pokemon back in Sword & Shield. Originally evolving from being given one of two special apples, a third apple named the Syrupy Apple was added to the Teal Mask DLC of Pokemon Scarlet & Violet.
Pokemon Scarlet & Violet DLC: How To Evolve Dipplin Into Hydrapple
Fan speculation turned out right! Dipplin gained an evolution. Hyrdapple can be yours with just one little item in Pokemon Scarlet and Violet's DLC.
