I saw a post regarding 3ds rom hacking earlier. And to answer some queries, yes you can in fact import custom models for 6th gen rom hacking. You can also be creative
3DS] Pokemon ROM Hacks Collection | Code Donut
Pokemon Super Mystery Dungeon - Expanded - ROM - 3DS ROM Hacks - Project Pokemon Forums
5 Best Pokemon Nintendo 3DS ROM Hacks Of All Time
Pokemon 8BitBros Edition - A NEW 3DS Hack Rom with Full Custom Music and New Characters, New Fun - YouTube
3DS] Pokemon ROM Hacks Collection | Code Donut
THE LEGENDARY APPEARS! • Pokemon 8bitBros Edition Nuzlocke (3DS Rom Hack) - YouTube
Pokémon Parallel Platinum - a 3DS ROM Hack for Alpha Sapphire set in a Parallel Hoenn! (Discord and Pokémon Direct in comments) : r/PokemonROMhacks
POKEMON RAYLESS RUBY & SHADOW SAPPHIRE! Huge New Pokemon Rom Hack Games!? - YouTube
5 Best Pokemon Nintendo 3DS ROM Hacks Of All Time
Just figured out how to install Rom Hacks onto my 3DS. Went a bit loco with it. : r/PokemonROMhacks
Argentum Moon (Ultra Moon Rom Hack) - ROM - 3DS ROM Hacks - Project Pokemon Forums
Top 3 Best Pokemon 3ds rom hacks for Android and PC | Citra Emulator | Ranking Pokemon 3ds Roms - YouTube
3DS Pokemon GBA ROM Hacks! (Virtual Console!) - YouTube
Los mejores hack roms de Pokémon de 3DS - XGN.es
3DS] Pokemon ROM Hacks Collection | Code Donut
Pokémon Rayless Ruby (3DS)
TOP 10 HACK ROMS DE POKEMON COMPLETOS EN ESPAÑOL PARA 3DS (ANDROID Y PC) - YouTube
Pokémon Parallel Platinum - a 3DS ROM Hack for Alpha Sapphire set in a Parallel Hoenn! (Discord and Pokémon Direct in comments) : r/PokemonROMhacks
El HACK ROM POKéMON MAS PROMETEDOR de 3DS! - [Brock] - YouTube