To reproduce:

1. create-react-app <your_project>
2. yarn add @elastic/eui @elastic/datemath moment
   (in my case this installs v13.7.0)
3. copy/paste some boilerplate code. I used https://elastic.github.io/eui/#/layout/page
4. yarn start

For versions 13.7.0, 13.6.0, 13.0.0 this gives import errors such as
buttonColor is not exported from button.js

Note:

• this doesnt happen for v12.4.0 - works perfectly fine
• i dont know if this makes a difference but I didnt test with typescript, i used plain JS