I don't quite understand as I haven't used OPC UA data types before, but sounds interesting.
There's always the option of extracting out the tags from TIA into Excel and creating your tags semi-automatically with the help of XML generating code (or json I suppose these days). I use this to create bulk udt instances, or even udts if I don't have a plc connected. There's an initial time investment to create the code, but once it's done, I've used it hundreds of times.
Alternatively, you could also use ignition's scripting to create tags in the same way with the system.tag.configure function.
This might give you some inspiration