User blog comment:DaNASCAT/Technical Update: September 16, 2015/@comment-4129195-20150916204630/@comment-24473195-20150917120119

@Kirkburn: Perhaps Energy X is asking for something like Wikimedia "InstaCommons",  a "instacommons" playlist widget might be worth looking into.

One of the little known features is that linked wikias can in fact share content (this has to be requested though), although it always depends on one wikia being a central repository and others pulling content from it, so it is not bi-directional.

Perhaps something like "WikiaTunes widget" with a playlist and such would be suitable. Given the 300000 wikias there's bound to be a few wikias producing original media.

Another approach would be to always submit this content to wikimedia commons (if it has a CC0 or CC-By-Sa) license. Wikimedia's VE upload wizard is certainly being redesigned with this purpose in mind (all free content to commons).

P.S. It is odd that no help page seems to talk about instacommons or even "interwikia content sharing". Perhaps it is to deter people from pulling in explicit content or reduce broken file links, if they are deleted from commons or any wikia.