Mirror Cubemap image for SkyLight

I’m using a Texture Cube image (UTextureCube) for a Cubemap in a SkyLight component and I’m looking for a way to flip horizontally or mirror the TextureCuve image. If it was a regular Texture or a material that seems to be pretty easy. But the Cubemap image parameter on a SkyLight will only take a Texture Cube asset.

I looked at the docs for the UTextureCube and it doesn’t even appear to be possible to access the raw pixel data in C++. Is there any way to do this?

I am generating the Texture Cube image at runtime, which is why i can’t just take the image into Photoshop and flip it and reimport…

thx-e