No definitely seen as zen mode only activates after you go below half hp
Plus it wouldn't work well as a wall seen as walls are very defensive which use defensive and recovering moves or items such as leftovers
Though darmantion zen mode does have high def if you want a wall you would normally give a item like leftovers which recovers hp and that's no good if you want zen mode because if it's hp goes over half it returns to normal mode
Though you should keep it it's a good sweeper in normal form but don't have two
Hope this helped