Textures assigning to incorrect part of model

I am importing a halo ringfor my project (the game will be free as per Microsoft’s Game Content Usage Rules) and am having an issue with the the materials rendering on the wrong piece.
The ring is 2 parts (one for each texture). The first part is for the outer ring texture and the second is for the inner ring. The issue is that when I import the ring’s FBX file, the materials (textures) will assign themselves to the opposite part.

Before you suggest switching the materials manually, I can’t do that because the parts are different shapes which means that the textures do not look right. Any solutions?

From the description, I think it is an issue of wrong axis data during export and/or import. As an example, in Blender, the default camera-facing axis is different from the default camera-facing axis of Unreal Engine. So, to export from Blender, it may require changing the default axis from, say, -x to +x…and +y to +z for the vertical axis in 3D space. Since these axes maintain those references upon export, the other engine (e.g., Unreal Engine) uses the references and may not automatically change them to the UE defaults so they’re correct for the model/material in the 3D space of UE. The halo ring is likely using different XYZ coordinates than the XYZ system in Unreal, and it’s not being converted properly. Before checking the export settings of the ring, if possible, what are the import settings in Unreal that are used?

It could also require unwrapping the UVs of the mesh inside Unreal, and then re-wrapping them to the correct coordinates and settings.