Coming Up Roses is a side quest in Pokemon Legends: Arceus. This quest will ask you to “Find the Pokemon with a scythe on each arm”. You will need to catch one of these and bring it back to Hiemo on Ramanas Island.
If you are unfamiliar with the full Pokedex of Pokemon this one may take a bit of work as the Pokemon he is referring to is not particularly common in the region, so you may not have come across one and may not come across one unless you are an avid explorer.
What Is the Pokemon With A Sythe on each arm?
The Pokemon that Hiemo is referring to is a Syther. This is a large bug type Pokemon that is bright green and hovers around using its wings. It does stand out but since it only lives in the deeper parts of the woods, you may not come across it too often.
You can actually find a Syther nearby next to the large tree arena. Check out the map below to see the exact location to use to find a Syther.
You will need to head off the beaten path around the Grandtree Arena. When you walk up the path edge, you will need to go deeper in to the trees and you will spot a few of these floating around.
Hiemo Isn’t Detecting Collected Syther
I am not sure if this is a bug or not but after you have captured a Syther and returned to Hiemo to hand in the quest, he will just repeat the initial line asking you to find a Pokemon with a Sythe on each arm. Even though you have captured one or more, he does not let you give it to him.
Unlike most other quests that allow you to use a Pokemon from your pasture, you must visit Hiemo when you have a Syther in your party. Seems strange that this happens but you must go back to a camp and change your party to include a Syther in your party before returning to Hiemo to give him the Pokemon that he is looking for.