weird shadow from reference mesh

Hellou, here I am again with a problem. My new mesh in game has the shadow from the reference mesh I used to transfer weight, which I'm pretty sure I did it wrong since this is my first time making a full body outfit. I'm still a bit confused as to what I'm supposed to do with uv_0 and uv_1 when making a full outfit. If I remember right I transfered weight using uv_1 which was probably wrong lol sorry  I made sure to remove the shadow, specular etc. just to make sure that was not the problem but that didn't seem to be the problem.

Here's the package file simfileshare




This is the dress I used for transfering weight


Thank you