This is a fork and use script to import contact lists from anywhere to Mailcoach list, be it self-hosted or Mailcoach SaaS you should be good with this.
Just have these as first three columns in your excel sheets - email, first_name, last_name
Add your Mailcoach credentials in a .env file before running the script.
MAILCOACH_API_KEY=
MAILCOACH_BASE_URL=
You're free to fork or use it however you wish, this is licensed under GPL v2 or later.