Skeletal Mesh stretching and deforming

I have a metahuman character and I’ve edited the shorts slightly in blender to better fit my needs, I wanted to just replace the old shorts and slot them on as all the weight painting is the same, the animations work in blender and in the skeletal mesh preview. But when I swap the legs out on the character this weird stretching issue happens and I don’t know how to fix it. I’d really appreciate any help on this. Thank you.


Original Metahuman Shorts

New Shorts (Same weight paint, working in engine)

Stretched, deformed mesh