Pokemon Sword UV Maps not exporting?

[Rukio]

before saying it has no uvs, have u edited the textures?(or the uvs)
they need to be mirrored, like, for example i did it with frosmoth
https://sta.sh/018xzqn9i6x7

I have not edited anything besides the name of the files. I named the files accordingly (Eyes, body, etc).
I wasn't aware I was supposed to mirror the textures. The eyes for example are a full sheet. I also don't have photoshop or anything.
So hows the process go?

I need to just mirror the textures and then apply them? I also didn't know I was supposed to touch the UVs. Nor do I know how to edit the UVs. I suppose I'm missing a few steps here.
In Blender, all the vertex groups are everywhere. The eyes look to be at the very top. I'm assuming I need to stretch them and match them for all the files???