Thanks for the additional explanation.   To pursue this approach, you will need to create/host copies of the Lr data, which is possibly not what you want.  We are not actively pursuing additional public sharing options here via our APIs. -Peter

Please take a look at the Connections capability in the left-hand panel of Lightroom (desktop).  It is located just below People.  You can send photos from Lightroom to  Adobe Portfolio using this capability.  Let us know if there's more that you are looking for here. -Peter