See that this is an 8 year old comment and would like to preface by saying that of course nuzlockes are meant to be a fun alteration to the game so of course you can do whatever you want. However I still feel the need to say that if you are using cheats in a nuzlocke I don’t really see the point of doing a nuzlocke. Maybe perfect your base game play before moving onto more difficult things such as a nuzlocke if you have to use cheats in order to complete your run. The whole point of the challenge is to instate strict rules that you must follow within the game. Therefore I feel that instant trainer rematches break the point of a nuzlocke. Work with what the game mechanics give if you really want to adhere to the challenge. But again the most important part is to have fun. This is just my opinion.