Federated Sharing Data Size

I am looking to modify my Nextcloud configuration. I currently have one instance with all data but am considering moving to two. One would have documents (server A) and the other media (server B). Server A has limited storage.

If I federated the two servers, would server A copy the media data shared to it from server B, effectively duplicating the data?

If so, is there a better proposal with Nextcloud to handle this scenario?

Iwant to maintain Nextcloud for the picture and video uploading from mobile devices. The other motivation is to have Nextcloud operating on a VPS instead of a home server for less downtime for services like Talk.