Some sort of PLC simulator would be needed to do what you want to do. I understand your need for something that would convert an OPC tag to a memory tag and then back. The problem with that would be storing the OPC Item Path somewhere. And if the PLC program is “a work in progress” then these OPC Item Paths could be changing anyways.
i am replying 8 years later but solution would be using reference tags in your template and using script to switch between opc and memory tags ie. script will write the source tag path in the reference tags.
The OP's request to be able to convert tags to memory tags and later back to OPC tags works today. And preserves the OPC-specific properties in the meantime. No reference tags or scripts required.
For Modbus and Logix v21+ drivers, there are third party server modules that use compatible OPC item paths. This means the driver instance can be deleted and created with the other type, same device name, and the OPC tags just work. In a pinch, these drivers can be stood up on another Ignition gateway (in trial, even) and given the IP addresses of the original PLCs so the normal drivers can be tested.
@pturmel i am curious if you know if its possible to create a script which would recursively list all the tags in specific folder in a loop (folders/subfolders etc) and wrote to the source property doing effectively the swap between OPC or memory simulation tags?
If this is possible i need to make a small party as it would mean the end of donkey work while writing the script which puts the value to the source tag path in the reference tags...