Things You Must do For All 3D Models

Set unit scale to .01 Meters (for proper unreal importing)

All models must have -Y as its forward axis

Name all objects (RTP_ObjectName)

Name all materials (RTP_ObjectName_MaterialName)

Pack the .blend file with any textures used, if textures where used

Apply all transforms

The origin point is at the base of the model and at the world origin