[Question] A couple questions

So I have 2 questions regarding making a fan game,

1. Do we need Nintendo's approval even if the Pokédex is nothing but fan made Pokémon, and we don't ask for cash in any way?

2. What program do people use to make the games that look a lot like the official ones? (Excluding RPGM if there's another engine)

1. No, you do not. That doesn't mean that you can sell it or gain any money from the game. If you want money, simply give your game a different name to stay away from the Pokemon brand.

2. I've used lots of engines before, but I think RPGM is the easiest for creating a Pokemon game. To answer your question, people use RPGM with Pokemon Essentials commonly, but there are a few different engines a game might use.

the first question has been asked already but the answer was "no" we don't need Nintendo's approval you can maybe consider this illegal if you want to but I would mostly call it inspiration of fans? Maybe. Also other then rpgmaker xp people take the route of rom hacking although I personally don't think it's good path and a lot of people have said that it also has it's limitations. Also some people use 3D engines to create some Pokemon games like Unity or Unreal Engine. However, taking that route would take long since you will have to make a lot of coding, there was someone that said that was making like a pack for Unity but I often forget who it is. I hope this helps you and if you need any future help if you take the game development path feel free to pm me.