@Katofhyrule12 , changing the texture will make the shine much less noticeable. I made some quick screenshots to demonstrate this. This is a dress from the Store, which is coloured just in plain colours and, to me, looks like it has an unpleasant rubbery texture:
https://i.imgur.com/bD1jUJK.jpg
This is what it looks like with some EA patterns from the Fabric section:
https://i.imgur.com/Zz65igu.jpg
https://i.imgur.com/jOvGmHs.jpg
The textures are, of course, just painted on, but they make it look like light is reflected in a different way from the fabric.
This is an excellent site for custom patterns with various fabric textures - the ones on the green knitted dress in my screenshot come from there:
https://www.simlicious.com/sims-3-downloads/patterns/