I would suggest asking N64 emulator developers. Modern emulators might have graphic dump functionality built in that would allow the meshes to be dumped in standardized and easy to use containers.
Like mentioned before, it may be possible to directly export model files from the 3DS rom as, like most modern Nintendo platforms, it should be its own file system with named file content once mounted in the appropriate file system software.
This really is not an appropriate site to ask such a question. Not that people are not willing to help you, just it is unlikely anyone can as this is highly specialized knowledge.
Apparently one way of dumping N64 models involves tricking Emulators into using a logging graphics API. That way the meshes get logged and can be used externally. However since this involves the use of a third party DLL I am sceptical that it is not a rouse for malware. Additionally it may not work with modern emulators or emulators that have software graphics only.
If one can get a graphic debugger and attach it to the used API of an emulator one should also be able to dump textures and meshes. This only works well on modern APIs such as programmable shader pipelines in D3D8/OpenGL or later so some old emulators will likely not work.