Wouldn't it be possible to just have one styling package maintained by one team for all other teams?
The question is, are the efficiencies gained more than the added friction/overhead. In our case, the answer was no. So we moved away from micro-frontends.
Sure, it's possible to remove all dependencies from a teams project by copy and pasting the code or by reinventing the wheel, but I'm not sure if these options are better than carefully chosen dependencies (including some maintained by other teams).