How to import props from blender?

hey there. i have struggle importing a prop from blender to unreal engine. i post the export and import settings down here. pls say with options i need to import the prop without that the polygones inside the helmet get deleted? :7 ty

i solved it. the problem are unmerged vertiges or the 2 sides setting in the object setting in unreal engine.

Good news for you but could you please describe how you resolve this problem?Because I got the same problem doing an model for ultius and don’t know how to do it.