When an object whose class has the EditInlineNew specifier is added to an instanced property, any children of the blueprint will have a reference to the same object that was created for the instanced property. This ends up causing issues related to setting values on the object as it affects the parent even if the changes are made in the child.
This can be resolved after creation by saving and reloading the project
This could be related to [Link Removed]
This also occurs in 4.17.2
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-52849 in the post.