I put together a tutorial of how I am developing Wagtail CMS sites locally and then deploying it to PA using a git push deployment.
There's a GitHub version of the tutorial here: https://github.com/wagtail-examples/tutorial-deploy-pythonanywhere-paid and I also put it on my own website here: https://www.nickmoreton.co.uk/articles/deploy-wagtail-cms-to-pythonanywhere/
I was inspired by this blog post: https://blog.pythonanywhere.com/87/
If anyone has any feedback about it please feel free to drop me a note here :) I hope it helps someone!