In the project, I already have created and used 4k proxies in sequences. I use a NEXIS storage system to store all media for the Project.

I have not started yet but would like to convert all proxies to 1080 (on a new NEXIS workspace which is different to where the 4k proxies are located), then delete all 4k proxy files from our Nexis (to save space. However there are other 4k proxies for other projects stored on the same workspace) and then reconnect all media in all bins to the new 1080 proxies. This would include ensuring all our sequences has its media reconnected.

How can I achieve this?

do you have access to the original files?  Can you link to them and make new 1080 proxies?

I was able to test and find how to do this. However is there any way of being able to relink all media in the project instead of having to go into each bin and then doing it?