This page offers a guide on how to complete Request 51: Coming Up Roses in Pokémon Legends: ARCEUS (PLA).
This request can be picked up from Hiemo, who’s found on Ramanas Island in Obsidian Fieldlands. You’ll only be able to reach Ramanas Island once you have access to Basculegion. Hiemo will ask you to find him a Pokémon with scythes on its arms.
Where to Find Scyther in Arceus
The Pokémon in question is a Scyther - the first Frenzied Noble (Kleavor) you fight is the new evolution of Scyther. Scythers can be found near Grandtree Arena in Obsidian Fieldlands and there’s even an Alpha Scyther nearby too!
Once you’ve got yourself a Scyther, show it to Hiemo. You’ll need it to be in your party for Hiemo to recognise that you’ve caught one. Once you’ve shown him the Scyther, the quest will be completed and you’ll be rewarded x1 Mastery Seed.