Modbus Devices

I am new on Modbus.
I am dealing with two inverters (with slave addresses 1 and 2) which send their parameters to the same modbus addresses. For example, they both send the output current to the modbus address 4x0017. How the master modbus device distinguish between these two parameters?
Modbus Rule: Modbus slaves are silent unless spoken to.

Modbus Rule: The Modbus master sends a command that either requests data or writes data to a slave.

Modbus Rule: The slave responds with either the data requested or an acknowledgement that the data was received and written.

Inverter/drives are usually Modbus slaves. Assuming yours are slaves and they are similar if not identical brand/models, then each probably uses the same register map, where the current output is in a Holding register, in your case, probably register # (4)0017.

The master polls one of the drives, waits for a reply, does something with the data in the reply message (saves it somewhere, probably with a tag) and then polls the other drive, waits for its reply and then does something with the data in that reply. Since the master knows which slave it polled, it should know what to do with the reply data.

The master might put the data in a register named (4)0017, but I doubt it, since (4)0017 is the typical format for a Modbus Holding register in a slave. I suspect that the drive's electrical current value is in register (4)0017 in the each of the slaves.

It doesn't matter to the master that different drives use the same register number, because the reply message will be from a specific drive, the one that was polled/addressed, not the other drive, because slaves are silent unless spoken to.
It doesnt matter that the slaves have the same registers. The master will read the data, and then store it locally at a place at its own choosing. Masters do not use the register model for their own storage; instead they store the received data somewhere in a PLC variable, or output of a function block.