What about Mow Rotom, Kartana, Virizion, Zarude, Tapu Bulu, and Calyrex? I'd also argue to that Pokemon like the grass starters, Leafeon, Wormadam, aren't really plant based, because they're really just animals with plants on them. Also, just because Regigigias, Oranguru, and Komala hold something related to plants doesn't mean that they are plant based in the slightest. Same goes for Kartana. It's not directly plant based, even though it may be related. By that logic, Pancham and Pangoro are also plant-based.