How to bundle Freemium Apps?

I have 5 apps in the store that I want to bundle in the Apple Store:

  • 2 are paid -> I could easily bundle them
  • 2 are freemium, i.e. basic version is free, upgrade with in-app purchase
  • 1 is free

I wanted to bundle the two freemium apps with a retail price of USD 0.00, but it seems that only subscriptions can be bundled. Am I doing something wrong? What is the best practice for bundles in general and for bundles with different sales models?

Thanks for your help and support!

How to bundle Freemium Apps?
 
 
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