You can use this plugin for PKHeX to inject the trainer data into your own save file.
Get the trainer files from here:
English Trainers https://github.com/projectpokemon/EventsGallery/tree/master/Released/Gen 3/ENG/e-Card Trainers
Japanese Trainers https://github.com/projectpokemon/EventsGallery/tree/master/Released/Gen 3/JPN/e-Card Trainers