Signing embedded framework not working in Xcode 11.2.1
Nested frameworks are not supported on iOS (see technotes). The only legit solution at the moment is to link "embedded" frameworks directly to a hosting app.
*XCFramework is mainly an aggregation of platform specific binaries' and has nothing to do with embedding frameworks unfortunately.
You gotta embed Alamofire to your project, too.
For example, you are using Carthage and the Cartfile of your framework has Alamofire library. You gotta use the same Carfile for your main app, too. Also, you gotta perform other Carthage actions(linking library, adding run script) for the main app.