ios – Firebase not recognized in AppDelegate of my Flutter plugin

I wrote a Fluter plugin which shows native screens and in some I use Firebase which i do initialize in the ios/Classes/AppDelegate.swift file.
The problem is that when I run the example app I get No such module 'Firebase' on its import.
I did implement auth, analytics and crashlytics in the plugin .podspec file as:

Pod::Spec.new do |s|
  s.name="my_native_screens_plugin"
  s.version          = '0.0.1'
  s.summary          = 'A new Flutter plugin project.'
  s.description      = <<-DESC
A new Flutter plugin project.
                       DESC
  s.homepage="http://example.com"
  s.license          = { :file => '../LICENSE' }
  s.author           = { 'Your Company' => '[email protected]' }
  s.source           = { :path => '.' }
  s.source_files="Classes/**/*"
  s.dependency 'Flutter'
  s.dependency 'Firebase/Analytics', '10.9.0' 
  s.dependency 'Firebase/Auth', '10.9.0'
  s.dependency 'Firebase/Crashlytics', '10.9.0'
  s.dependency 'MBProgressHUD', '1.2.0'
  s.dependency 'PanModal', '1.2.7'
  s.dependency 'TouchDraw', '2.1.2'
  s.dependency 'MaterialComponents/Snackbar', '122.0.1'
  s.dependency 'MaterialComponents/TextFields', '122.0.1'
  s.dependency 'MaterialComponents/TextFields+Theming', '122.0.1'
  s.dependency 'MaterialComponents/Cards', '122.0.1'
  s.dependency 'MaterialComponents/BottomNavigation', '122.0.1'
  s.dependency 'MaterialComponents/Chips', '122.0.1'
  s.dependency 'MaterialComponents/Chips+Theming', '122.0.1'
  s.dependency 'MaterialComponents/Tabs+TabBarView', '122.0.1'
  s.dependency 'MaterialComponents/Buttons', '122.0.1'
  s.dependency 'YPImagePicker', '5.2.2'
  s.dependency 'SwiftRichString', '3.7.2'
  s.dependency 'IGListKit', '4.0.0'
  s.dependency 'SDWebImage', '5.13.1'
  s.ios.vendored_frameworks="kotlin-mpp/kotlin-mpp/build/cocoapods/framework/kotlin_mpp.framework"




  s.platform = :ios, '14.0'



  # Flutter.framework does not contain a i386 slice.
  s.pod_target_xcconfig = { 'DEFINES_MODULE' => 'YES', 'EXCLUDED_ARCHS[sdk=iphonesimulator*]' => 'i386' }
  s.swift_version = '5.0'
end

I did try to add s.dependency 'Firebase/CoreOnly', '10.9.0' as well as I saw it in the official Firebase packages, but it didn’t make any difference..

Can you spot if I’m doing anything wrong in the .podspec file??
Many thanks
Cheers