Requires Babel “7.0.0-0” but was loaded with “6.26.3”

Test which version you are running with cmd

babel -V

If it is not verion 7 or higher

npm uninstall babel-cli -g
npm uninstall babel-core -g

And

npm install @babel/cli -g
npm install @babel/core -g

If you are using Jest run

npm install babel-core@7.0.0-bridge.0 --save-dev

Uninstall and reinstall @babel/node solves the problem if you do node development.