I created a shortcut (and small dockerized API) to create simple barcode cards for Apple wallet.
It will prompt you to customize it. If you use the same name and the same barcode then when you re-run this shortcut it will replace any existing one with the same name and barcode. The logo replacement works best if you can image search a logo and select that when choosing one.
Here is another one I made with defaults for a place I go often called Bar K.
Generate Bar K Apple Pass: https://www.icloud.com/shortcuts/f5448973270340ca86e9f0b2471e44f4
They both use this API and my developer certificates to create them: https://github.com/shauder/apple-wallet-shortcut
Docker container: https://hub.docker.com/r/shauder/apple-wallet-shortcut
Anyone can host the API themselves and modify the URL in the shortcut.
Example of how it looks: