For the BFRES file format which Nintendo uses then there is
this which has 3DS Max Script for model importing/Viewing. Most Nintendo games should use this (ARMs, MK8D, Mario and Rabbids, ect) as it's like BCH from 3ds, or BFRES from Wii U. There is no way of knowing how much different the format would be for Pokemon games however, they could use their own depending on the engine they use.
Also keep in mind any newer games than 3.0 you will have to wait awhile since they're currently not possible to rip without a newer exploit.