One of the announcements from WWDC 2020 was that Family Sharing will be available for IAP and subscriptions:
How can we enable this and is it only available in iOS/iPadOS 14?And in addition to shared family app purchases, the App Store now supports Family Sharing for subscriptions and in-app purchases. This is great for developers who offer content for the whole family to enjoy.
Family Sharing for in-app purchases will be available later this year. You will be able to enable Family Sharing for auto-renewable subscriptions and non-consumable in-app purchases in App Store Connect.
For more information check out the below WWDC 2020 sessions:
What's new with in-app purchase
https://developer.apple.com/videos/play/wwdc2020/10661
What's new in App Store Connect
https://developer.apple.com/videos/play/wwdc2020/10651/
For more information check out the below WWDC 2020 sessions:
What's new with in-app purchase
https://developer.apple.com/videos/play/wwdc2020/10661
What's new in App Store Connect
https://developer.apple.com/videos/play/wwdc2020/10651/