Global Design (typography / Colors) Change for existing project?

Basic Design Question:
How can I change the typography / Colors of my existing project across without at a global level, without doing it component by component.

Eg:

  1. Change all body text from Inter (default) to Roboto
  2. Change all Blue 600 (default #hex) to Yellow (#my hex)

Ideally you would be using Typography or Color styles for your elements, then you can easily change the values in the style settings