I wish I noticed this sooner but arrow keys work in the game :D I've updated the game instructions to let players know they aren't limited to WASD
Viewing post in Mystery Dungeon - New Beginnings jam comments
That's what I thought since you are using Unity. Also if you are not using these keys for something else, you can assign the horizontal and vertical axes in the Unity inputs to both WASD and ZQSD (which is the Azerty equivalent), by simply duplicating these axis and giving them different possibilities.