With EAS Build it should be possible, in theory. I have never used Branch myself, so not sure exactly what’s entailed normally or with NativeLink. If you can list the specific things that would need to be done to a plain React Native project to integrate NativeLink support then someone should be able to say what would be required of a Config Plugin to do the same in a managed Expo app that can then be built with EAS Build. (There’s a misconception that EAS Build is only available if you pay for the Expo Priority Plan. That is the easiest way to use it, but you can also use
eas build --local to build locally on your own machine, in which case you don’t need to pay Expo.)
Also, it might be worth contacting Branch and pointing to the Config Plugin docs in case they’re willing to write one so that their users can use it in a managed Expo app without having to write their own plugin.