Hello Addeuss sorry for late reply,
I haven't got custom ue.4.22 or bns original files anymore.
I think you need everything to be present in whatever head folder your uncooking so for example if your uncooking jinf head make sure all content is there eg, JinF_001 folder with JinF_001_Skeleton, JinF_MorphTargetSet folder with all Morph Target files, JinF_001_Physics and JinF_001 skelmesh.
Always right click the skeleton asset first (JinF_001_Skeleton) next right click on JinF_001 skelmesh, if editor not crash ...Decook.
Next go into JinF_MorphTargetSet folder and create a new folder, select all morph target files and copy them to the new folder, save new folder.
Duplicate JinF_001_Skeleton (create new folder, select JinF_001_Skeleton copy to new folder) save every thing, close ue4.
(In explorer) Delete cooked files and replace with duplicated /uncooked files (same thing with JinF_MorphTargetSet) open ue4 and everything should work, BnS models need the _MorphTargetSet folder and contents to work, maybe because it was ported from ue3?
If none of the above help then maybe video here
https://www.gildor.org/smf/index.php/topic,7101.15.html will.
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