A Token of Gratitude is a request in Pokemon Legends: Arceus. You will speak with Medi and she will tell you of a Pokemon that she met long ago that guided her home when she was lost in the field lands. She wants you to go and find out if the Pokemon is still there.
You will need to search around the field lands, which are quite large to find a patch of specific flowers where the Pokemon had lived. Here is what you need to do to find it.
Where To Find The Field of Flowers
The place that Medi is referring to is the Floaro Gardens. This is found in the northwest corner of the map, to the left of the main camp here. You can climb over the cliffs and you will get there fairly easily. Check out the map below for the exact location.
You will notice a large brown circle in this area but there are no flowers here. It seems that everything has died. You will need to make your way to this brown circle and it will trigger a rather happy and cute event that will allow you to see the Pokemon that is being referred to as part of this quest.
You will need to capture the Pokemon that Medi remembers to finish the quest. Once you have done this, you will be able to complete the quest and have a nice memory and a rather interesting Pokemon to add to your Pokedex.