As long as file names remain the same and you don’t accidentally overwrite your camera raw files you will be able to link. Eek!
PR Proxy is just a codec; that being said, if you go into media encoder, there is a box that should say “match source” so if you are editing with 4k, your proxies will be 4k so that when you create your graded string out, any movement/rescaling will easily translate over when you paste attributes. Does that make sense? Hopefully that answers your question.
Lisa Bradley
Editor/Videographer