Moving shared family purchases to a new shared account

I’m currently the Organizer of our 3-person Family and am sharing subscriptions from my Apple account that we all use. We also have a child account. What I want to do is to use a new Apple account only for purchases, transfer all existing shared purchases made on my Organizer account over to it, and have that account be used in our Family sharing.

I’ve looked into migrating from a secondary account to a primary account and it seems what I want to do is the reverse. I’ve also looked into secondary Apple accounts used with Family sharing but I don’t think that would migrate over the purchases I’ve already made and I want to continue sharing the purchases I’ve already made on that account.

Is it possible to do what I’m trying to do?