Imported FBX with skeletal mesh cause problem with UE4 materials (UE4.26.1)

I have a weird problem. After importing FBX with any skeletal mesh made in blender 2.83 to UE4.26.1, I get error in most of automotive materials (free Epic pack). Before import everything works fine.
If I import the same file but with unchecked skeletal mesh option - materials works fine. I’ve checked new, very simple file (just two cubes and bone) too. Still have a problem.
EDIT: In UE4.25.4 everything works perfect.
EDIT2: I’ve made brand new instalation of UE4.26.1. Problem still exists.
EDIT3: Model imported to UE4.25.4 scene and then opened in UE4.26.1 as a copy - works perfect.

Please ignore this if you already using these tools - but on a side note consider installing the epic blender tools - They really do make the export/import process way smoother and may fix this issue.

Note: You will need to associate your Github account with the epic GitHub account (which can be done in your epic profile settings) to access these tools. Otherwise, when you click this link it will show as private.