Eventually, your trainer and Hop will figure out that you need Honey itself and not Nectar in order to make the Max Soup that will help your Urshifu be able Gigantamax when in battle. With that in mind, you will go hunting for a Vespiquen. Hop will suggest heading to Honeyclam Island, which is found in the far northwest waters of the Isle of Armor. Once there, you won't find any Vespiquen out in the open. Instead, you will have to shake the tree in hopes of finding one. After you do, however, you will be challenged by a Dynamaxed Vespiquen. Defeat it with any Pokemon you would like (simply put them at the lead of your Party), and you will receive the sticky honey you were looking for.