Both games are way, way, way too dependent on their online connections.
All you can do in PGA 2K23 without an internet connection is play local rounds at TopGolf or at the 2K Official courses - none of the user-made courses can be played. You can also work in the designer, but cannot publish a course.
All you can do with EA when not connected to the internet is play a quick round at any of the courses:
https://youtu.be/33yBbXeq8GI
Both of these games basically become coasters if you don't have an online connection. It's unfortunate, but it's the way of the world these days.