Superyoshiom
Smash Master
As much as I love Decidueye, Mimikyu's got a couple of things going for itI have to agree. It might be my bias as a Mimikyu/Lycanroc supporter, but I honestly think Gen 7 has so many viable candidates for Smash that an "upset" fighter of some description is honestly more likely than specifically Decidueye. Decidueye is honestly not that heavily promoted at all outside of Pokkén DX, isn't THAT popular compared to other Gen 7 Pokémon in Japan, and feels a bit too much like Smash fans are filling quotas that Sakurai is about to break.
1) It's marketable as all heck
2) It's very hard to make into a clone of Pikachu (Ghost/Fairy type, and while I do believe it can learn thunderbolt and thunder by TM, it can't learn any of Pikachu's moves by level up), which can give it a very unique moveset and playstyle
3) It has the potential for an awesome final smash