Unity FBX Export can export in runtime? any idea plz help me,can i fbx export in runtime ?

Hi guys, first , Sorry to my english... I making a customizing app in Unity.

and i want to fbx export function in runtime. because, when i export (customizing Character), i apply the other app . (Target Platform is andoroid or IOS)

but I think Unity FBX Exporter is only use in Editor. isn't it?

anyway... Does anyone have an idea?

or It's not possiblity?

I'm confuse these days :(

plz help~