People use powersaves and pkhex instead of action replay now since but I don't know what has happen with that particular brand. Pretty much the Powersaves have replaced the action replay for the 3DS games but you can also use pkhex to gen other stuff.
Edit: Forgot that powersaves and action replay are the same since I haven't used it in over a year now.
Basically you just need to download the powersaves guide which should be on on their site and follow the directions shown. Btw back up your game first! The is important in case you happen to mess up with powersaving anything in like max rare candies or cloning. For the cloning method. I think you just have to make space for the Pokemon you have to clone and not have any other mom at a particular space otherwise the desired Pokemon will overwrite the other.
Edit: Forgot that powersaves and action replay are the same since I haven't used it in over a year now.
Basically you just need to download the powersaves guide which should be on on their site and follow the directions shown. Btw back up your game first! The is important in case you happen to mess up with powersaving anything in like max rare candies or cloning. For the cloning method. I think you just have to make space for the Pokemon you have to clone and not have any other mom at a particular space otherwise the desired Pokemon will overwrite the other.