You might want to get in touch with the Hovawart Club Schweiz to ask for a recommendation for a ZH List 1 trainer.
http://www.hovawart.ch
I see that there is a Hovawart breeder in ZH; that might be a good contact. Since his/her puppies sold to ZH owners will need to do the List 1 courses hopefully he/she knows which ZH trainers have experience with the breed.
All the best!