I have 12,000 images organized by year / folders in 1 LR Classic catalog. In Adobe Portfolio I have two galleries each with 8 collections, based on a topic/theme. These are uploaded to Portfolio via LR collections. Each collection has many "very good" images in them. So I created another category collection named the same as the collection but adding the word best. I dragged from the parent collection to the best. These are the images upload Portfolio. I can quickly add or remove to the "best" collection and upload changes. This is what makes Portfolio more attractive to me.
Problem is the images are not reduced in size nor have a watermark logo. I add watermarks and convert to jpgs as an export in LR.
I would like to be able to export the "best" version of a collection to another LR collection ie "best reduced watermark". In all the "best" 16 collections we are talking max 200 photos. I do use stars, keywords etc but the LR collections are the best import option to Portfolio.
I do not find an option to export to a collection or any forum suggested workaround other than catalogs. I see keeping all these collections, Portfolio and catalogs in synch an expanding work flow problem.