Kinda related, I'm working on a block list item picker (BLIP) which allows selecting a block on Node A from a block list property on Node B. Stores a ref to the original block so changes to that block's content will be reflected on Node A. Value converter ensures the BLIP property value is returned as a block list model for consistency.

I was thinking about the need for this type of thing just yesterday. One hurdle is that we render via partials that match the element alias. (e.g. ImageFeature alias calls ImageFeature.cshtml from partials) and how the BLIP would return the correct partial... though I suppose the BLIP partial could then call the correct partial for the [linked to] content.

I think the latter would work - isn't that how the default block list rendering is managed? When rendering a blip property, models builder will provide a regular block list model, so whatever works for blocks will work for blip