How to automate creating pull request for same fixes in multiple repositories

Question

We have 5 repositories A, B, C, D, and E, each repository has a master branch. I want to add the word "fix" to the master branch of each repository from the single fix branch. How this can be automated to create a "fix" branch from the master branch for all repositories and add the word "fix" into the fix branch and then create a pull request for all repositories.