To answer my own question: It's not possible. Official statement from Razer: To answer your question, the reason why Synapse is only detecting one Kiyo Pro is that both Kiyo Pro's are using the same driver, and Synapse is programmed to detect both Kiyo Pros as one because of the driver.

I haven't tested it myself after receiving the answer from Razer though bc I'm going to return the product.

Sadly I don't have this information, I gave it further to our community, so maybe another user can answer.