Hello.
I can make your project as a python application, I can make the application read your CSV, Excel or other file, as you prefer.
And I can use the necessary connection data to create the application to write in the database of your Wordpress installation according to the authentication data that you provide, this can be a configuration, so that you can change the authentication data when you consider it necessary.
We can initiate a dialogue, and create the application that is most convenient for you, in order to have a program with which you are satisfied, and that can scale as you wish.
I hope to work with you on this project, greetings.