If your question is asking how to get these moves onto Roserade, then here is my answer:
To get Leaf Storm onto your Roserade, breed it with either Exeggutor (Kantonian or Alolan) or Tropius, who are both in the Grass egg-group and can learn this move through level up. As for Sleep Powder, Carnivine is the only Pokémon (except for the Budew line) to have this move as an egg-move only.
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But, if your question is asking for moves that do the same thing (or simply put, a replacement) as Sleep Powder and Leaf Storm that Roserade can learn, then here is my answer:
The only move that put opponents to sleep (and can be learnt by Roserade) is Grass Whistle, which is an egg-move of Roserade's.
The only move that is "similar" to Leaf Storm (and can be learnt by Roserade) is Energy Ball.