Could you use cocoapods and subspecs?
Pod::Spec.new do |s|
s.name = "Umbrella"
...
s.default_subspec = 'A'
s.subspec 'A' do |ss|
ss.frameworks = '.......'
end
s.subspec 'B' do |ss|
ss.frameworks = '.......'
end
end
If someone wants to use the Umbrella.A
framework then they refer to it like this in their Podfile
pod 'Umbrella/A'