Not free and not expensive but is doing a great job on relinking bitmaps, corona proxies, xrefs is Library Track / Relink by Pixamoon.
One of the great features it has is that you do not have to open the Max file.
https://www.pixamoon.com/shop/4587562584/library-track-relink-.../9337230
I can confirm it too, we use this tool all the time in our offcie, and it is working flawlessly. Not only that you don“t need to open the MAX files you need to relink, but you can also "batch relink" many of them at once, for example, a collection of trees from your library, or somthing like that. It has many options, one of them is similar to the "Relink Bitmaps" script, automatically search for maps inside a given location, but it also has the option to "set path strip", so you can change just the part of the local/network adress you need, for example changing the unit letter, or the IP adress, etc.
And I agree again, imho, it is not expensive for the use we give to it.