This could have partial usefulness for sub VIs, but not for plain LabVIEW items (who would want to do a global replace of all "add" with a "multiply"...
😉Unlike in text based languages, "replace" is not such a clear cut operation. What do do if the terminals don't match? Often, it requires a manual cleanup.
There are a few workarounds, depending on how your VIs are organized. Are both in user.lib?
For example, if you really need to replace a subVI in a complex application, save it as development distribution, quit LabVIEW, then use explorer to temporarily rename the obsolete subVI and replace it with the new VI using the old name. Now re-open the toplevel VI, doubleclick any instance of your new subVI and give it the new more appropriate name. Save e
verything again and all will be updated to call the new subVI using the new name.
Now rename the old subVI back to what it was so other projects that use it don't choke.