Not really- proxies made for corona are without any material with a really low poly meshes. When you linking it, what I did, it import almost no data to Blender, only base mesh. When you are linking from other Blend file a model with for example cycles materials it imports textures to.
Not sure if I understand your question. However, I bought RTX 2080 ti and I fall in love with Cycles. I need to finish another project before Christmas and for sure I will use Cycles for it. In the color variations for other client I need 2 minutes for a one siding variation in 4k In Corona it tooks 10 minutes but Corona is CPU based which isnt so powerful as a new Nvidia:)
Thanks for the links, didn’t know them Especially linking arrayed collection from the same Blender file