UE4 4.2 Importer flips normals from Blender

Recently updated my project to UE 4.21 and have been bothered by the fact that new importer imports some of the normals flipped. Yes, the objects have negative scales in Blender however prior I was able to do this and export into UE4 with no issue. It’s an important part of my workflow that I can have some objects with negative scales as I can reuse object data and flip it to create variation.
Is there some new feature or check box that I must tick off in order to fix this issue. I’ve attached some examples of what’s going on.

We get exactly the same issue now we’ve moved to 4.21 (but we export fbxs from Maya). It’s pretty annoying as we use referenced objects in our models so freezing their scale transformations to be non-zero is not ideal.
UE4 has never done this in the past but now a ton of our models are borked if we reimport them.

We’d also love to know if there’s a flag or workaround on import to address this.