I didn't want to use cocoapods, since I haven't used it for a long time in native iOS development. So what I am doing right now is this:
• Create an interface in the multiplatform environment
• Create a way to access the implementation inside the multiplatform environment (can be a shared var or a factory of some kind)
• Then inside Xcode create a class which implements this interface
• Then also inside Xcode inside the App init or the AppDelegate set this class for your shared var or implement the factory method to return your custom class.
This way you can use SPM and use expect actual. I found this the best way to use 3rd party libraries.