It’s not possible, no.
The closest thing is the ability to create an Ignition OPC tag with an arbitrary OPC Item Path, which depending on what OPC server you’re talking to, may be able to dynamically create and read or subscribe to data with that NodeId.
This is how the modbus driver works, for example. There’s no browsing, so you just create tags with item paths you know (or think you know, anyway) exist, and the modbus driver starts trying to read from that modbus address.